#3584 PTB *(t/d)uŋ ⪤ *ts(y)uːŋ MIDDLE / CENTER / INSIDE / NAVEL

This etymon was originally set up as *tsyuːŋ in STC #390, on the basis of Lushai (Mizo), Bodo, and Dimasa forms. Benedict later revised this to *tuːŋ (STC n. 63, p.17), and specifically banished WT gźuŋ as probably not cognate. This reconstruction was also adopted in HPTB pp. 287, 310. It seems clear that the most ancient version of this root had a simple or palatalized dental stop, as witnessed by the certain Chinese cognate 中 GSR #1007a-e ti̯ông/t̑i̯ung ‘middle’ (see below). From an early date, however, many languages developed a sibilant or affricate initial before this medial vowel ‑u‑, in a manner reminiscent of a phenomenon in modern Japanese, where the phonemic syllable /tu/ has come to be pronounced [tsɯ]. The same variation between stop and (af)fricate initials before ‑u‑ is to be found in ‘mortar’ PTB *(t)sum, with most reflexes pointing unambiguously to PTB *tsum (e.g. WB chum, Lahu chɛ, Lushai (Mizo) sum), while Jingpho thùm reflects *tum. See also #526 PTB *(t)sum NAVEL.

For convenience I am here assigning the reflexes of this etymon into two allofamic roots, according to whether they have retained a stop initial (#3447 PTB *(t/d)uŋ ⪤ *(t/d)waŋ) or have undergone initial frication (#1628 PTB *ts(y)uːŋ).

The semantic range of this word-family includes the notion of CENTER (as does the phonologically unrelated root #517 PTB *m/s‑la(ː)y NAVEL / CENTER / SELF [q.v.]).

The *‑u‑ ⪤ *‑wa‑ variation posited for this root is paralleled in several other etyma, e.g. #2009 PTB *nu‑(ŋ/k) ⪤ *nwa‑(ŋ/k) HORN, #359 PTB *tuk ⪤ *twak HEAD / SKULL / NECK, and #2379 PTB *s‑kyuːr ⪤ *s‑kywaːr SOUR / BE ACID. (See HPTB:513-514.) This variation parallels the *‑i‑ ⪤ *‑ya‑ alternation found in a number of roots, notably #33 PTB *s‑myak ⪤ *s‑mik EYE.