Central Ok

Timothy Usher, Santa Fe Institute

Situation

The Central Ok family consists of two or three closely-related languages spoken in villages along the Sauw River and its tributaries in the Merauke Regency of Indonesia's Papua province (Hughes 2009: 11-14.) The designations Nakai, Naki and Tangko are the words for “what?” in each language (q.v. Wilbrink 2004: 109f, 110f, Hughes 2009: 37.)

Subclassification

The internal classification of Central Ok is as follows:

Central Ok

Tangko

Nakai-Naki

Nakai

NakI

Sources

Jang (2003: 39-47) 239 comparative terms for Nagi of Kawor 2 village

Wilbrink (2004: 109a-110f) 239+ comparative terms for Sait (Nagi) and Nakai after Menanti

Hughes (2009: 27-37) 239 comparative terms for Tangko of Kawemaot village and Nakai of Burunggop

Williamson (2010) grammar of Nagi

History of classification

The Central Ok family was first recognized by Hughes (2009: 3,) who calculated a 29-32% lexicostatistical resemblance between Tangko of Kawemaot and Nakai of Burunggop.

Historical phonology

Proto-Central Ok had perhaps 14 consonants and 6 vowels as follows:

*m *n
*p *t *s *k [*kʷ]
*mb *nd *ŋg [*ŋgʷ]
*w *r *j
*i *u
*e *o
*a

Any consonant except apical non-stop /*r/ can occur initially. Prenasalized apical stop /*nd/ is found in only a small number of examples, in which it is initial. Even though this is in complementary distribution with /*r/, and medial reflexes of Ok /*nd/ have merged those with /*r/, for historical reasons they are not shown here as allophones of a single phoneme, although such an equivalence may be synchronically justified.

Consonant clusters do not occur except across morpheme boundaries in compounds.

Only a restricted set of consonants occurs finally:

*m *n
*p *t *k
*ŋg
*r *j

Initial consonants correspond as follows:

Central Ok Tangko Nakai Naki
*m- m m m
*n- n n n
*p- p [ɸ] ø ø
*t- t t t
*s- s s s
*k- k k k
*kʷ-
*mb- mb mb mb
*nd- nd nd nd
*ŋg- ŋg ŋg ŋg
*j- j j j
*w- w w w

Medial consonants correspond as follows:

Central Ok Tangko Nakai Naki
*-m- m m m
*-n- n n n
*-p- ? ? ?
*-t- r t t
*-s- s s s
*-k- k k k
*-mb- mb [b] w w
*-ŋg- ŋg ŋg ŋg
*-r- r r ø
*-j- j j j
*-w- w w w

Final consonants correspond as follows:

Central Ok Tangko Nakai Naki
*-m m m m
*-n n n n
*-p p p p
*-t s ø t t
*-k k k k
*-ŋg ŋg [ŋ] ŋg [ŋ] ŋg [ŋ]
*-r r t j
*-j ø j j

Vowels generally correspond as follows:

Central Ok Tangko Nakai Naki
*i i i i
ɯ i i
*u u u u
*e e e e
*o o o o
*a a a a

These correspondences are exemplified as follows, with Tangko attestations drawn from Hughes (2009: 27-37,) Nakai from Hughes (2009: 27-37) and Wilbrink (2004: 110a-110f) and Naki from Jang (2003: 39-47) and Williamson (2011 ibid.) Jang's, Wilbrink's and Hughesˈ survey vocabularies are phonetic transcriptions; Williamson's are orthographic. For clarity of presentation, the general dispositions of initial consonants will presented first, then those of medial consonants, then those of final cononants, followed by those of vowels. Some details of the forms which follow are necessarily tentative.


[under contruction – Hughesˈ Nagi to be replaced with Jang]

Any consonant except apical non-stop /*r/ can occur initially.

Initial bilabial nasal /*m/ is retained as such in all descendants:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*m- m m m m
star *mit-kor mir-kor ˈmiːt-qɔt̚ˈmiɾ-qo
nose *mito ˈmɛɾu mitɔ ˈmitɔ ˈmiʔtɔʔmito
burn/cook *mij- miˈɾ- ˈmiɽ- mir-
near *mep mep-
net bag *men mɛn mɛn mɛn men
that/there *me-te mɛtɛ- mɛtɛ- ˈmɛtɑ
blue (?) *mʉk mɯq mik mik
hot *mamʉn mæˈmɯn mamɪn ˈmæmin mɑˈmin mamin
come *man- man- ˈmɑːn- ˈmɑn- mane-
grandchild *makop ˈmɑʁɔp mɔˈʔɔp magop
ten *maji[n/ŋg] malɪŋ mɑːˈl̪in mɑˈɽiŋ mariŋ
big *maja[t/r] mɑⁱˈjɑɾ malar mæˈʝæt mɑˈjɑr mazar
mother's br.*mom mom
spittle *mok mal-moq mɑɢ-mɔk
blunt/dull *mo[r/j]o molo ˈmɔɽɔ ˈmoɽo moro
behind *m[o/y]t mɯ-qɔl̪ɔ-ˈbɔɾ mɔˈɽ-ɑɽɛt mor
breast *muk muq mʊk muk̚ muk̚
one/all *muwim ˈmʷɪɴ-ɢi ˈmim-kimʷim(-ki)

Initial apical nasal /*n/ is retained as such in all descendants:

Central OkTangko Nakai Nakai Nagi Nagi
*n- n n n n
tooth *n[i]ŋgi ˈnɑɴi ˈniŋgiˈniŋginiŋgi
1 sg. *ne nɛ-ɾ ne nɛ̃ ne
mother *naŋg nɑn nɛ-naŋ nɑ̃ŋ nɑ̃ŋ naŋ
crocodile *naŋgarup nɑɴqɑˈl̪upnɑˈɴɢɑlup̚
rattan/rope*n[a/o]ŋg nɑɴ-ˈqɯ nɔ̃ŋ nɔɴ ɴɔŋ noŋ
bird *noj nɔh ˈnø̃ɛ nɔˈɛ nʷɛ nʷe
1 pl. *nu(-p) nɥ-ɽ nup̚ nup̚ nu(-p)

Initial bilabial plain stop /*p/ is fricated to [ɸ] in Tangko and dropped in Nakai, a pattern of loss shared with West Ok and Lowland Ok:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*p- ɸ ø [ʔ ʕ]ø ø
this/here *pe ɸɛ- ˈʔɛ-
forearm/seven*pet et̚ er
sharp *pʉt ɸɯ-ˈjæn ir it̚
new *pap ɸɑːp-ˈqɔab-nɪm ˈɑːb-imˈɑw-iˈˈgi
wind *paptʉ ɸɑɸˈtɯ
mountain *pa[r/j]ʉmɸɑˈlɯm alɪm ˈʕɑɽim ɑːɽim
tongue *poŋg ɸɔŋ ɔŋ ʔɔŋ
wind *pup up̚ ʔuː up̚

Initial apical plain stop /*t/ is retained as such in all descendants:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*t- t t t t
get up/stand up*tip- ˈtiβ- tiˈw-
child *tena ˈtenɑ ˈtɛna tena
hole *t[a]mon ˈtɑmɔn
bite *tam- tɑn- ˈtɑm-
child *tan[i/e] tɑˈne tani ˈtɑni tani
cuscus *takip tɑˈɢip ˈtɑɢip ˈtɑʁip
shame/shy *… tarmor
tie *taj- tɑⁱdɛm tirɛm taze-
seven *tajap tɑⁱˈɾɑptadab tɑˈdʒɑp
down/below *to(-te) tɔ-le ˈtɔː-teˈto-tɛto-
flint *toŋg toŋ-
stone *tum tum tum

Initial velar plain stop /*k/ is retained in both as such in all descendants. It is often realized as uvular [q] and occasionally as voiced velar [g]:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*k- k [k q g] k k [k q] k [k q g] k
body *kit kit̚
eye *kir kiɾ ˈki-wɛ ki-we
coconut (?)*kitot qiˈso ˈqitɔt kiˈtor ~ ˈkitor
scratch *k[i]ŋg qiɴ-qiɴɢuˈd-
finger *kiri kiɾi ˈhil̪i ˈkiɾi
ear *kiroŋg kiˈl̪ɔŋ ~ qil̪ɔɴkera-su-katkɛˈrɛ-su ˈki-su ki-su
do *ke ke-
2 sg. m. *kep qɛp kɛp kɛp qɛp kep
hair *kep qɛp kɛp kɛp̚ qɛp̚ kep
pinkie/one *ket-ket kɛr-kɛr ˈkɛt-kɛt ker-ket
sago *kero qɛˈɾɔ kɛˈɽɔ tʃo keo
far *kam qɑːm kam qɑm qɑm kam
who? *kama kama ˈqɑmɑ kɑˈmɑ
cough *kanom kanom ˈkɑnɔm kɑˈnɔm
skin/bark *kat qɑ ~ qɑː kat ~ kar qɑt̚ ~ ˈkɑt qɑt̚ ~ kɑr
knowledge *kat qɑː qɑt̚ kɑt̚ kar
who? *katep qɑˈɾɛp-qɔ
person *kara ˈqɑɾɑ kala ˈqɑɽɑ ~ qɑˈɽɑqɑː ka
bandicoot *kajet ˈkɑɽɛr ˈkɑˈʝɛt
white *kajak kalaq̚ qɑːʝɑq qɑjɑk̚
stone *kawit qɑⁱⁱs kawi ˈqɑβit
young *kombet qɔˈbɛs ˈqɔwɛt
belly *komba kɔwa ˈkowɐ kowa
leaf *kon qɔːn kɔn ˈqɔn(-su) kon
ashes *kotep kɔtɛp ˈkɔtɛp qotɛp kotep
smoke *kok ˈqɔq
pig *koŋg qɔŋ kɔŋ qɔŋ kɔŋ koŋ
bone *koro ˈqɔɾɔː kɔrɔ ~ kɔlɔˈqɔɽɔ kɔ ~ qɔ ko
long *k[o/y][r/j]aŋgqɯˈɾæɴ kɔˈlaŋ qɔˈɽɑɴ qoɽɑŋ koraŋ
2 sg. f. *kup kup
sweat *k[u]sin kusin
heavy *k[u]kun kuɣun
woman/wife *kur qut ~ quɾ kut̚ ~ kur qut̚
die *kuwi- kɔˈdʲɔɾ ʍui-ˈsɛt ˈkʷi-sɛ kʷi-sɛr kui- ~ kʷi-
louse *kuwip gɯp̚ kʷip̚ qʷip kʷip̚
night *kuwin- qɯnɔˈɾɛɾ kʷinɛsɛr ˈgunese kʷine-

Initial laminal /*s/ is retained as such in all descendants:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*s- s s s s s
hear *(weŋg-)s- βɛŋ-sɛsiɸ ˈβɛɴ-sɛm ˈwɛŋ-sɛm veŋ-se
up/above *sip(-te) si-te ˈsiːp-te ˈsip-tɛ sip-
old/before*sin ˈsiːn-qɔ siŋ-gɪ sin sin(-ˈki) sin-
right *sinim siˈniːn sinim ˈsinim ˈsiːnim
mud *sambit-tek-teksæbi-teˈteq sɑbit̚-tɛk̚tɛk̚
bandicoot *sakor ˈsɑʁoɽ sɑɢʷɛ
three *sa[r/j]ep-kut sɑɾɔ-ˈquɾ sali-kud-ɛnˈsɑːlip-ut̚ˈsɑrop-kur sarop-kur
sit *sup-n- ?sɔɴ- subn- ˈsun- ˈsubn- supne-

One apparently irregular example is likely a loan from Dumut:

Central Ok TangkoNakai Nakai Nagi Nagi
HughesWilbrinkHughes Jang Williamson
*[t/s]-t s s
leech*[t/s]eren teˈɾen ˈsɛl̪ɛnsɛn

Initial prenasalized bilabial stop /*mb/ is as in other subgroups of Ok typically realized as plain voiced [b]:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*mb- mb [mb b] mb [mb b]mb [b]mb [b]
wing *mbiru ˈbiɾu mbɪru ˈbiɽu bju
older brother*mb[e]
elbow/knee/8 *mbaŋgup bɑˈɴup ~ bɑɴup̚baŋgup ˈbɑɴɢup ˈbɐɴɢup
mosquito *mbajeŋg bɑⁱɴ ᵐbɛ̃ŋ
lip(s) *mbon-kat mbɔɴ-qɑ bon-koɾ
run *mbʉr- bɯl-ɑˈn-

Initial prenasalized apical stop /*nd/ is uncommon:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*nd- nd [d]nd [d]nd [nd d]nd [ɖ]nd [d]
dig *ndik-m- digmisib digˈmɛm dikmɛm
cloud *ndep dɛːp dɛp ndɛp̚ ɖɛp̚
not/no*ndo -ndɔ -dɔ ɖɔ do

Several examples known to have initial /*nd/ or /*r/ in other Ok subgroups are here indeterminate between /*nd/ and /*j/ (below):

Central Ok TangkoNakai Nakai Nagi Nagi
HughesWilbrinkHughes Jang Williamson
*[nd/j]- d d d
sand *[nd/j]ikin diɣin ˈdiɢin digin
path *[nd/j][y]jip diriɸ diˈl̪ip
*[nd/j]- l
heart*[nd/j][y] lubɪb

“Heart” might be thought a loan, as expected vowel /*y/ is reflected as /u/ in Nakai rather than as /i/ (below.)

Initial prenasalized velar stop /*ŋg/ is somewhat more common than it is in other Ok subgroups. As with /*k/, it is often realized as uvular [ɴɢ ɢ], or in Tangko as nasal [ɴ]:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*ŋg- ŋg [ɴ k]ŋg [ŋg g ;k]ŋg [ɴɢ ɢ]ŋg [ɴɢ ɢ k]
cold *ŋgit gir ɢit kiːɾ gir
ant *ŋgasom ɴɑˈsɔm ˈɴɢɑːsɔm ˈŋɢɑsom
garden *ŋgosan kɔˈsɑn kɔsan ˈɴɢɔsɑn
wrist/joint/six*ŋgoŋg ɴɔɴ ŋgom ɴɢɔɴ ~ ɴɢoŋ ɢɔŋ ~ -ɴɢoŋ ŋgoŋ

“Cold” and “wrist/joint” can be traced to proto-Ok, or alternately are loans from Mountain Ok. “Ant” may be a loan from Dumut or vice-versa. The examples of “cold” and “garden” suggest that the contrast between initials /*k *ŋg/ is disappearing.

One example is a loan from Indonesian:

Central OkTangko Nakai Nakai NagiNagi
Hughes Wilbrink HughesJangWilliamson
g- ŋg [ɴ]ŋg [g]
saltgaram ɴɑˈɾɑm garam garam

Initial bilabial non-stop /*w/ is occluded to [β] in Tangko and Nakai but not Naki, especially when followed by front vowels /*i *e/:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*w- w [w β]w [w β]w [w β]w v ø
name *wini wiˈni ˈwini vini
egg *wirin βiˈɾin βirim βiˈl̪in ˈwiɾin
speech *weŋg wɛɴ βɛŋ βɛɴ ~ βɛŋ wɛŋ ~ weŋveŋ
left *wasot wasor ˈwɑːsɔt ˈwɑsor
mud *wasuk βɑsuq
bamboo knife*waki ˈwɑʔɑⁱ ˈwɑɣi vaki ~ vagi
left *waŋg[a]n wɑˈɴɑn
vomit *wajan βalan
grass skirt *w[o]n[o]m onom

Initial palatal non-stop /*j/ is is occluded in all descendants:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*j- j [j dʲ d]j [d dð l]j [dʒ dz]j [d ɖ ɽ ɺ]z
red *jamu damu ˈdʒɑːmu ˈjɑmu
urine *jamun ˈjæmuːn ˈdzæmun ˈdɑmun
good *jap jæp̚ dðap dʒæp ɖɑp zap
female *… zaŋgʷi
breadfruit*jawot jɑˈwɔs ˈdʒɑːβɔt ˈɺɑwor
fishnet *… zarum
seed *jop dʒɔp
foot/leg *jon diˈjɔn dɔn ~ lɔn dʒɔn ˈdon zon
handle *joko zoko
garden *joŋg ɽoŋ-ˈbip̚ zoŋ-bip
banana *jup dup̚ dʒup̚ dup̚
thorn *jʉk dɯq dðɪk̚ dʒik dɪk

The occlusion of /*j/ is shared with Ninggerum to the southeast, where Lowland Ok /*j/ is realized as [d r].

The quality attested by the following correspondence is not yet known. It remains a problem in Lowland Ok as well, from which it is conceivably a loan:

Central OkTangkoNakai Nakai Nagi Nagi
HughesWilbrinkHughes Jang Williamson
*… ndʒ ŋgʲdzŋge
flesh/meat*…om ndʒɔm ŋgjɔm dzɔm ŋgeom

Any consonant can occur medially except rounded velar /*kʷ/, which didnˈt occur medially in Proto-Ok, and prenasalized apical stop /*nd/, which has been merged with non-stop /*r/. Medial bilabial stop /*p/ was rare in Ok, and has not been found to occur.

Medial bilabial nasal /*m/ is retained as such in all descendants:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*-m- m m m m
weep/cry *am- ʔɑm- am- ˈʔɑm- ˈɑʔm-
see *ak-m- ʔɑˈm- ˈʕɑʕm- ˈɑk̚m-
hot *mamʉn mæˈmɯn mamɪn ˈmæmin mɑˈminmamin
bite *tam- tɑn- ˈtɑm-
hole *t[a]mon ˈtɑmɔn
shame/shy*… tarmor
who? *kama kama ˈqɑmɑ kɑˈmɑ
red *jamu damu ˈdʒɑːmuˈjɑmu
urine *jamun ˈjæmuːn ˈdzæmunˈdɑmun

Medial apical nasal /*n/ is retained as such in all descendants:

Central Ok Tangko Nakai Nakai Nagi Nagi
*-n- n n n n
eat/drink *en- ɛn- ~ an-ʔɛˈn- eˈn- ene-
dog *anon ʔɑnɔːn anɔn ʔɑnɔːnˈɑnon anon
bush/forest*anoŋg ʔɑˈnɑɴ anɔŋ ɑˈnɔŋ anoŋ
walk/go *on- ʔɔˈn- on- ʔɔn- oˈn- ~ ˈɔʔn-one-
come *man- man- ˈmɑːn-ˈmɑn- mane-
child *tena ˈtenɑ ˈtɛna tena
child *tan[i/e] tɑˈne tani ˈtɑni tani
right *sinim siˈniːn sinim ˈsinimˈsiːnim
sit *sup-n- ?sɔɴ- subn- ˈsun- ˈsubn- supne-
cough *kanom kanom ˈkɑnɔmkɑˈnom
night *kuwino-serqɯnɔˈɾɛɾkʷinɛsɛr ˈgunese
name *wini wiˈnio ˈwin vini
grass skirt*w[o]n[o]m onom

No native examples of root-medial plain bilabial stop /*p/ have been identified.

Medial plain apical stop /*t/ is merged with /*r/ in Tangko:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*-t- r [ɾ l]t t t
locative *-te -le -te -tɛ
father *itaŋg itaŋ ˈʔitɑŋ ʔiˈtɑŋ itaŋ
hand/arm *itu iˈtu ˈʔutu ˈʔituʔ ~ ˈitu
short *atu[p/k] ʔɔˈɾuq atup ʔɑːtup̚ɑʔˈtuk̚
sun *aton ʔɑˈɾɑn aˈtɔn ˈʔɑtɔn ɑʔˈʈon aton
sharp/bad*atut ˈɑtur atur ˈʔɑːtut atur
nose *mito ˈmɛɾu mitɔ ˈmitɔ ˈmiʔtɔʔ mito
who? *katep qɑˈɾɛp-qɔ
ashes *kotep kɔtɛp ˈkɔtɛp qotɛp kotep

In one example, /*t/ is fricated to /s/, probably due to preceding /*i/ as is the rule in Ngalum:

Central OkTangkoNakai Nakai Nagi Nagi
HughesWilbrinkHughesJang Williamson
*-t- s t t
coconut (?)*kitot qiˈso ˈqitɔtkiˈtor

Medial laminal /*s/ is generally preserved as such in all descendants:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*-s- s s s s
fire *asi[n/ŋ] ˈʔæsin ~ ɑˈsiɴaˈsin ˈʔɑsiɴ ɑˈsiŋ asiŋ
sweat *k[u]sin kusin
ant *ŋgasom ɴɑˈsɔm ˈɴɢɑːsɔmˈŋɢɑsom
garden*ŋgosan kɔˈsɑn kɔsan ˈɴɢɔsɑn
left *wasot wasor ˈwɑːsɔt ˈwɑsor
mud *wasuk βɑsuq

Medial plain velar stop /*k/ is generally lenited between vowels in all descendants:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-k- k [ɢ ʁ]k [ɣ ø]k [ʁ ʔ ʕ]k [g ɣ ɢ ʁ]k [k g]
this/here *iki ˈiɣi ~ iːˈɣi
sleep *ak- ʔɑˈɢ- aɣ- ʕɑˈʕ- ɑˈʁ- akai-/akore-
pitpit sp. *akup agup
moon *okor ˈʔɔʁɔl ɔr ʕɔˈʕɔt oʔɢʷɛ okoe
grandchild *makop ˈmɑʁɔp mɔˈʔɔp magop
cuscus *takip tɑˈɢip ˈtɑʁip ˈtɑɢip
dig *ndik-m- digmisib digˈmɛm dikmɛm
bandicoot *sakor ˈsɑʁoɽ sɑɢʷɛ
heavy *k[u]kun kuɣun
bamboo knife*waki ˈwɑʔɑⁱ ˈwɑɣi vaki ~ vagi
sand *jikin diɣin ˈdiɢin digin
handle *joko zoko

The general loss of medial /*k/ in the Lowland Ok languages to the southeast should be viewed as a continuation of ths areal trend.

Medial prenasalized bilabial stop /*mb/ is reflected as plain voiced [b] in Tangko and merged with the reflexes of /*w/ [w β] in Nakai, a development shared with Ninggerum:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*-mb- b w w [w β ø]w [w ø]v
hit *amb- (?) ʔɑⁱɛm βɛm ɑim ve-
laugh *ambian ʔæbiæɴ- ʔɑβiɑn ɑjɑˈn- ajane-
village *ambʉp ˈʔɑbɯ-bɔɾ ɑⁱp̚ ˈɑip̚
sky *ambʉr ɑˈbuɾ awir ʔɑːˈβit ɑˈwi
head *amb[o/u][t]ˈʔɑbuɾ awor ʔɑˈβɔt ɑwo-qɔ avo
umbilicus*[k]ambin gavin
young *kombet qɔˈbɛs ˈqɔwɛt
belly *komba kɔwa ˈkowɐ kowa
tail *[w][e/a]mbʉʔɛˈbɯ wawi ˈwɑːβi ˈwɑwi

As in Mountain Ok, the reflexes of medial apical prenasalized stop /*nd/ have merged with those of /*r/ (below).

Medial prenasalized velr stop /*ŋg/ is often reflected as uvular [ɴɢ], or as merely [ɴ] in Tangko:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-ŋg- ŋg [ɴ ɴq] ŋg ŋg [ŋg ɴɢ]ŋg [ŋg ɴɢ]
tooth *n[i]ŋgi ˈnɑɴi ˈniŋgi ˈniŋgi niŋgi
crocodile *naŋgarup nɑɴqɑˈl̪up nɑˈɴɢɑlup̚
elbow/knee/8*mbaŋgup bɑˈɴup ~ bɑɴup̚baŋgup ˈbɑɴɢup ˈbɐɴɢup
left *waŋg[a]n wɑˈɴɑn
female *… zaŋgʷi

Medial apical non-stop /*r/ is typically dropped in Naki, a loss shared with Ninggerum:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-r- r [r ɾ ]r [r l]r [r ɽ l l̪]ø ø
wing *mbiru ˈbiɾu mbɪru ˈbiɽu bju
crocodile*naŋgarup nɑɴqɑˈl̪up nɑˈɴɢɑlup̚
leech *[t/s]erenteˈren ˈsɛl̪ɛn sɛn
ear *kiroŋg kiˈl̪ɔŋ kera-su-katkɛˈrɛ-su ˈki-su ki-su
sago *kero kɛˈɾɔ kɛˈɽɔ tʃo keo
person *kara ˈqɑɾɑ kala ˈqɑɽɑ ~ qɑˈɽɑ qɑː ka
bone *koro ˈqɔɾɔː kɔrɔ ~ kɔlɔˈqɔɽɔ kɔ ~ qɔko

There is at least one exception:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*-r- r [ɾ]r r [l̪]r [ɾ]
egg*wirin βiˈɾin βirim βiˈl̪in ˈwiɾin

Medial palatal non-stop /*j/ is typically occluded, becoming nearly indistinguishable from the reflexes of /*r/ (above):

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-j- j [j dʲ ɾ ø]j [r l d]j [ʝ dʒ ɽ l̪]j [j ɽ]j
canoe *ajep ʔɑˈɛp ˈʔɑːɽɛp ɑˈɽɛp̚
hold *ajep- ʔɑˈɸ- aɾ- ʔɑːr- ɑɾew-
bow *ajVn ʕɑⁱn ɑˈɽɛdzɔn ɑˈɽon azon
many *ajup ʔɑɾup̚ alu ʔɑːˈl̪up ˈɑɽup̚ arup
burn/cook*mij- miˈɾ-u mir- ˈmiɽ-
ten *maji[n/ŋg] malɪŋ mɑːˈl̪in mɑˈɽiŋ mariŋ
big *maja[t/r] mɑⁱˈjɑɾ malar mæˈʝæt mɑˈjɑɾ mazar
mosquito *mbajeŋg bɑⁱɴ ᵐbɛ̃ŋ
tie *taj- tɑⁱdɛm tirɛm taze-
path *[nd/j][y]jip diriɸ diˈl̪ip
bandicoot*kajet ˈkɑˈʝɛt ˈkɑɽɛr
white *kajak kalaq̚ qɑːʝɑq qɑjɑk̚
death *k[o]jor kɔˈdʲɔɾ kʷi-sɛr ʍui-ˈsɛt ˈkʷi-sɛ
seven; *tajap tɑⁱˈɾɑp tadab tɑˈdʒɑp
vomit *wajan βalan

Because the reflexes of medials /*r *j/ overlap in range, it's possible that some forms shown here with one really had the other.

Medial /*w/ is generally retained as such in all descendants:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-w- w [w ɓ ø]w w [w β]w [w ø]w
father's father*awi ʔɑˈɓɯ ˈʔɑβui ˈɑwi awi
cassowary *awon ʔɑˈwɔn aɣom [sic]ʔɑˈwɔn ˈɑwɔn awon
stone *kawit qɑⁱⁱs kawi ˈqɑβit
breadfruit *jawot jɑˈwɔs ˈdʒɑːβɔt ˈɺɑwor

Only a restricted set of consonants occurs finally, including nasals /*m n/, plain stops /*p *t *k/, prenasalized velar stop /*ŋg/, which as in other Ok subgroups is invariably realized as [ŋ], and non-stops /*r *j/.

Final bilabial nasal /*m/ is preserved as such in all descendants, excepting some instances when it is assimilated to [ŋ] when followed by a velar stop /*k *ŋg/ in a compound:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*-m m m m m
male/husband *im iŋ-gi im-ki
rain *am ʔɔm am-ga ˈʔæm-ɢɑ ˈɑm-ɢɑ am-ga
taro *om ʔɔm
mother's br. *mom mom
one/all *muwim ˈmʷɪɴ-ɢiˈmim-kimʷim(-ki)
mountain *pa[r/j]ʉmɸɑˈlɯm alɪm ˈʕɑɽim ɑːɽim
stone *tum tum tum
right *sinim siˈniːn [sic]sinim ˈsinim ˈsiːnim
far *kam qɑːm kam qɑm qɑm kam
cough *kanom kanom ˈkɑnɔm kɑˈnom
side of neck/11*kum kum
ant *ŋgasom ɴɑˈsɔm ˈɴɢɑːsɔmˈŋɢɑsom
fishnet *… zarum
flesh/meat *…om ndʒɔm ŋgjɔm dzɔm ŋgeom

Final apical nasal /*n/ is preserved as such in all descendants, excepting some instances when it is assimilated to [ŋ] when followed by a velar stop /*k *ŋg/ in a compound:

Central OkTangko Nakai Nakai Nagi Nagi
*-n n n n n
laugh *ambian ʔæbiæɴ-kɛˈɾ- ʔɑβiɑn ɑjɑˈn- ajane-
dog *anon ʔɑnɔːn anɔn ʔɑnɔːn ˈɑnon anon
sun *aton ʔɑˈɾɑn aˈtɔn ˈʔɑtɔn ɑʔˈʈon aton
bow *ajVn ʕɑⁱn ɑˈɽɛdzɔnɑˈɽon azon
cassowary *awon ʔɑˈwɔn aɣom [sic] ʔɑˈwɔn ˈɑwɔn awon
older sister*on ʔɔn ʔɔ-ˈɽɔp ɔ-ˈɾɔp
net bag *men mɛn mɛn mɛn men
hot *mamʉn mæˈmɯn mamɪn ˈmæmin mɑˈmin mamin
hole *t[a]mon ˈtɑmɔn
old/before *sin ˈsiːn-qɔ siŋ-gɪ sin sin(-ˈki)sin-
umbilicus *[k]ambin gavin
leaf *kon qɔːn kɔn ˈqɔn kon
sweat *k[u]sin kusin
heavy *k[u]kun kuɣun
garden *ŋgosan kɔˈsɑn kɔsan ˈɴɢɔsɑn
egg *wirin βiˈɾin βirim [sic]βiˈl̪in ˈwiɾin
left *waŋg[a]n wɑˈɴɑn
vomit *wajan βalan
grass skirt *w[o]n[o]m onom
sand *jikin diɣin ˈdiɢin digin
urine *jamun ˈjæmuːn ˈdzæmun ˈdɑmun
foot/leg *jon diˈjɔn dɔn ~ lɔn dʒɔn ˈdon zon

…:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
*-[n/ŋ]n ŋ [n ɴ] n ŋ [ɴ]ŋ ŋ
fire*asi[n/ŋ] ˈʔæsin ~ ɑˈsiɴaˈsin ˈʔɑsiɴ ɑˈsiŋ asiŋ
*-[n/ŋ] n n ŋ ŋ
ten *maji[n/ŋg] malɪŋ mɑːˈl̪in mɑˈɽiŋmariŋ

Final plain bilabial stop /*p/ is typically retained as such in all descendants:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-p p [p p̚] p p [p p̚]p [p p̚]p
inclusive *-p -p ~ -p̚ -p -p ~ -p̚ -p ~ -p̚ -p
canoe *ajep ʔɑˈɛp ˈʔɑːɽɛp ɑˈɽɛp̚
pitpit sp. *akup agup
many *ajup ʔɑɾup̚ alu ʔɑːˈl̪up ˈɑɽup̚ arup
house *[a/o]p ʔɑːp̚ ɔp ʔɔp ɔp̚ op
near *mep mep-
grandchild *makop ˈmɑʁɔp mɔˈʔɔp magop
new *pap ɸɑːp-ˈqɔ ab-nɪm ˈɑːb-im ˈɑw-iˈˈgi
wind *pup up̚ ʔuː [sic] up̚
elbow/knee/8*mbaŋgup bɑˈɴup ~ bɑɴup̚baŋgup ˈbɑɴɢup ˈbɐɴɢup
crocodile *naŋgarup nɑɴqɑˈl̪up nɑˈɴɢɑlup̚
cuscus *takip tɑˈɢip ˈtɑʁip ˈtɑɢip
seven *tajap tɑⁱˈɾɑp tadab tɑˈdʒɑp
up/above *sip(-te) si-te ˈsiːp-te ˈsip-tɛ sip-
cloud *ndep dɛːp dɛp ndɛp̚ ɖɛp̚
path *[nd/j][y]jip diriɸ diˈl̪ip
hair *kep qɛp kɛp kɛp̚ qɛp̚ kep
who? *katep qɑˈɾɛp-qɔ
ashes *kotep kɔtɛp ˈkɔtɛp qotɛp kotep
good *jap jæp̚ dðap dʒæp ɖɑp zap
seed *jop dʒɔp
banana *jup dup̚ dʒup̚ dup̚

Final plain apical stop /*t/ is fricated to [s], which is not otherwise known to occur finally, or dropped in Tangko:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-t s [s ø] t [t r ø]t [t t̚]t [t t̚ r]
sharp/bad *atut ˈɑtur atur ˈʔɑːtut atur
behind *m[o/y]t mɯ-qɔl̪ɔ-ˈbɔɾ mɔˈɽ-ɑɽɛt mor
forearm/seven*pet et̚ er
body *kit kit̚
coconut (?) *kitot qiˈso ˈqitɔt kiˈtor ~ ˈkitor
pinkie/one *ket-ket kɛr-kɛr ˈkɛt-kɛt ker-ket
skin/bark *kat qɑ ~ qɑː kat ~ kar qɑt̚ ~ ˈkɑt qɑt̚ ~ kɑr
knowledge *kat qɑː-qɛˈɾ- qɑt̚ kɑt̚ kar
bandicoot *kajet ˈkɑˈʝɛt ˈkɑɽɛr
stone *kawit qɑⁱⁱs kawi ˈqɑβit
young *kombet qɔˈbɛs ˈqɔwɛt
cold *ŋgit gir ɢit kiːɾ gir
breadfruit *jawot jɑˈwɔs ˈdʒɑːβɔt ˈɺɑwor
left *wasot wasor ˈwɑːsɔt ˈwɑsor

It's conceivable that these represent two correspondences reflecting finals /*t *nd/ respectively, as “young” and “breadfruit” are known to continue final /*t/ while “skin” is thought to continue /*nd/; if so these would be distinguished only in Tangko.

One example in which this does not occur may be a loan into either Tangko or Naki:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughesJang Williamson
*-[t/r]ɾ t r ɾ
big*maja[t/r] mɑⁱˈjɑɾmalar mæˈʝætmɑˈjɑɾmazar

Final plain velar stop /*k/ is often realized as uvular [q q̚]:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-k k [q]k [k k̚ q]k [k k̚ q ħ]k [k k̚ q̚]
water *ok ʔɔːq ɔ̄q ħɔħ oq̚ ok
blue (?)*mʉk mɯq mik mik
spittle *mok mal-moq mɑɢ-mɔk
breast *muk muq mʊk muk̚ muk̚
white *kajak kalaq̚ qɑːʝɑq qɑjɑk̚
smoke *kok ˈqɔq
thorn *jʉk dɯq dðɪk̚ dʒik dɪk
mud *wasuk βɑsuq

Prenasalized stops /*mb *nd/ do not occur finally because they have been merged with /*p *t/ (above).

Final prenasalized stop /*ŋg/ is realized as nasal [ŋ] in all descendants, as it is throughout the Ok family, or as uvular [ɴ]:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-ŋg [ŋ] ŋg [ŋ ]ŋg [ŋ]ŋg [ŋ ɴ]ŋg [ŋ]
father *itaŋg itaŋ ˈʔitɑŋ ʔiˈtɑŋ itaŋ
bush/forest *anoŋg ʔɑˈnɑɴ anɔŋ ɑˈnɔŋ anoŋ
tongue *poŋg ɸɔŋ ɔŋ ʔɔŋ
mosquito *mbajeŋg bɑⁱɴ ᵐbɛ̃ŋ
mother *naŋg nɑn [sic] nɛ-naŋ nɑ̃ŋ nɑ̃ŋ naŋ
rattan/rope *n[a/o]ŋg nɑɴ-ˈqɯ nɔ̃ŋ nɔɴ ɴɔŋ noŋ
flint *toŋg toŋ-
pig *koŋg qɔŋ kɔŋ qɔŋ kɔŋ koŋ
long *k[o/y][r/j]aŋgqɯˈɾæɴ kɔˈlaŋ qɔˈɽɑɴ qoɽɑŋ koraŋ
wrist/joint/six*ŋgoŋg ɴɔɴ ŋgom [sic]ɴɢɔɴ ~ ɴɢoŋ ɢɔŋ ~ -ɴɢoŋŋgoŋ
garden *joŋg ɽoŋ-ˈbip̚ zoŋ-bip
speech *weŋg wɛɴ βɛŋ βɛɴ ~ βɛŋ wɛŋ ~ weŋ veŋ

In one example. final /*ŋg/ is lost in Nakai when followed by /su/ “leaf”:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-ŋg ŋg [ŋ ɴ] ŋg [ø] ŋg [ø]ŋg [ø]
ear*kiroŋg kiˈl̪ɔŋ ~ qil̪ɔɴkera-su-katkɛˈrɛ-su ki-su ki-su

Final apical non-stop /*r/ is distinguishable from /*t/ by its palatalization and loss in Naki:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*-r r [ɾ ɽ l]t [t̚ r]t [t t̚]j [ɛ ø]j
emphatic *-r -ɾ ~ -ɽ
sky *ambʉr ɑˈbuɾ awir ʔɑːˈβit ɑˈwi
moon *okor ˈʔɔʁɔl ɔr ʕɔˈʕɔt oʔɢʷɛ okoe
fall (?) *ser -sɛr -sɛt ~ -set -ˈsɛ
bandicoot *sakor ˈsɑʁoɽ sɑɢʷɛ
eye *kir kiɾ ˈki-wɛ ki-we
star *mit-kor mir-kor ˈmiːt-qɔt̚ ˈmiɾ-qo
shame/shy *… tarmor
death *k[o]jor kɔˈdʲɔɾ
side of neck/11*kum kum
woman/wife *kur qut ~ quɾ kut̚ ~ kur qut̚
night *kuwino-serqɯnɔˈɾɛɾ kʷinɛsɛr ˈgunese

Nakai's merger of final /*r/ with the reflexes /*t/ is shared with Muyu-Yonggom to the southeast.

The reconstruction of final laminal glide /*j/ in the following two roots is highly tentative, as outcomparison to other Ok subgroups suggests /*r/; however in none of these does /*j/ otherwise occur finally, so it's possible that Central Ok preserves a distinction which has been neutralized in other subgroups. The alternative would seem to be that both Nakai words are loans from Naki:

Central OkTangkoNakai Nakai Nagi Nagi
HughesWilbrink Hughes Jang Williamson
*-j ø j [ɛ]j [ɛ]j [ɛ]
excrement*oj ʔɔː wɛ̄ wɛ̃ ŋgʷe
bird *noj nɔh ˈnø̃ɛ nɔˈɛ nʷɛ nʷe

No examples of bilabial non-stop /*w/ are known to occur finally.

High central vowel /*ʉ/ is retained as [ɯ] in Tangko and merged with high front /i/ in Nakai and Naki:

Central Ok Tangko Nakai Nakai Nagi Nagi
Hughes WilbrinkHughes Jang Williamson
ɯ [ɯ u]i i i i
sky *ambʉr ɑˈbuɾ awir ʔɑːˈβitɑˈwi
blue (?)*mʉk mɯq mik mik
hot *mamʉn mæˈmɯn mamɪn ˈmæmin mɑˈminmamin
wind *paptʉ ɸɑɸˈtɯ
mountain*pa[r/j]ʉm ɸɑˈlɯm alɪm ˈʕɑɽim ɑːɽim
sharp *pʉt ɸɯ-ˈjæn ir it̚
run *mbʉr- bɯl-ɑˈn-
thorn *jʉk dɯq dðɪk̚ dʒik dɪk
tail *[w][e/a]mbʉʔɛˈbɯ wawi ˈwɑːβi ˈwɑwi

Sequence /*uwi/ is reduced to /ɯ/ in Tangko:

Central OkTangko Nakai Nakai Nagi Nagi
Hughes Wilbrink Hughes Jang Williamson
*uwi ɯ uwi [ʷi]uwi [ui ʷi]uwi [ʷi i u]uwi [ʷi ui]
one/all*muwim ˈmʷɪɴ-ɢi ˈmim-ki mʷim(-ki)
die *kuwi- kɔˈdʲɔɾ ʍui-ˈsɛt ˈkʷi-sɛ kʷi-sɛr kui- ~ kʷi-
louse *kuwip gɯp̚ kʷip̚ qʷip kʷip̚
night *kuwin- qɯnɔˈɾɛɾkʷinɛsɛr ˈgunese kʷine-

Pronouns

Central Ok free pronouns are reconstructed as follows, with Tangko forms drawn from Hughes (2009: 28-29,) Nakai from Hughes (2009: 28-29) and Wilbrink (2004: 110a) and Nagi from Jang (2003: 40) and Williamson (2011: 12-14):

Central OkTangkoNakai Nakai NagiNagi
HughesWilbrinkHughesJangWilliamson
1 sg. *ne nɛ-ɾ ne nɛ̃ ne
2 sg. m. *ke-p qɛp kɛp kɛp qɛp kep
2 sg. f. *ku-p ? ? ? ? kup
3 sg. m. *e ɛ-ɾ ɛ ? ? e
3 sg. f. *u ? ? ? ? u
1 pl. excl.*nu nɥ-ɽ ? ? ? nu
1 pl. incl.*nu-p ? ? nup̚ nup̚nup
2 pl. *i-p ʔip̚ ? ʔip ʔip ip
3 pl. *i ʔi-ɾ i ? ? i

Verbal morphology

[under construction]