Comments:An Eastern isogloss; cf. notes to *si̯ŭ̀ŕi, *ši̯ŭŕu. In Korean we would rather expect *-ă- or *-u-/-o-; -ɨ- may be a result of vowel assimilation.
Comments:The Kor. reflex is irregular (we should expect *h-), perhaps due to the influence of the second -s-. It is alternatively possible to reconstruct *sisu with an irregular labialized reflex in PT (instead of *sɨs-), on analogy with *sub < *sɨb 'water'. One should also keep in mind that Middle Korean has actually two forms (sìs- 'wash' and sɨ́s- 'cleanse, wipe off') that have merged in modern s:it-, so we may in fact be dealing with a confusion of two original roots.
Comments:KW 332, VEWT 429. The Jpn. and Kor. forms (compared in Whitman 1985, 168, 236, and additionally in Vovin 2000 - although his further attempts to link the Kor.-Jap. root to PA *k`i̯ăli should be rejected) seem to fit here phonetically (although there is a tone discrepancy); as for semantics, one should probably reconstruct the original meaning 'suck', whence 'lick' and 'tongue' in the Eastern area. Medial *-j- has to be reconstructed to account for the loss of resonant in Kor.; it had also probably caused a dissimilation in the Western area (*si̯ōjri > *sōjri), which explains the -o-reflex in Turkic.
Comments:Владимирцов 160, АПиПЯЯ 27, 284. A Turk.-Mong. isogloss. Mong. *u-su can be explained as a normal dissimilation < *su-su ( < *sub-su); cf. similar cases in *sisegeji > *isegeji 'felt', *sü(t)-sü > *ü-sü 'milk', *sus- > *us- 'disappear, perish'. The relationship of the Mong. and Turk. forms is strengthened by the presence in Turkic of archaic derivatives *sɨb-sɨ-, *sɨb-sa-.
Comments:EAS 96, 144, SKE 36-37. Mong. is hardly < Turk., despite Щербак 1997, 145. Mong. and Kor. have an assimilation (*s- > *č-), usual for this type of roots. In Jpn. cf. perhaps OJ susu-pana, MJ sùsú-bànà 'snivel from the nose' (cf. mod. hana-kuso, lit. 'nose faeces').
