WEBMar 27, 2024 · 鎖骨 (sakotsu): the clavicle or collarbone. Etymology [edit] Probably from Middle Chinese 鎖骨 (MC swaX kwot, literally “fastening + bone”). First attested in Japanese in a text from 818. Pronunciation [edit] さ こつ [sàkótsú] (Heiban – [0]) さ こつ [sáꜜkòtsù] (Atamadaka – [1]) IPA : [sa̠ko̞t͡sɨᵝ]