Where does “sternocleidomastoīdēs” come from?

sternocleidomastoīdēs (New Latin) comes from Ancient Greek κλείς, from Proto-Hellenic klāwī́ds, from Proto-Indo-European kleh₂u- — nail, pin, hook - instruments, of old use for...

Ancestry of “sternocleidomastoīdēs”, step by step

sternocleidomastoīdēs traces back through 3 separate lines of ancestry.

via Ancient Greek κλείς

Step	Language	Word	Meaning
1	Ancient Greek	κλείς	Something used to lock/unlock: key, bolt, bar; A...
2	Proto-Hellenic	klāwī́ds	—
3	Proto-Indo-European	kleh₂u-	nail, pin, hook - instruments, of old use for...

via Latin sternum

Step	Language	Word	Meaning
1	Latin	sternum	The breastbone
2	Ancient Greek	στέρνον	breast, chest; seat of the affections, heart;...
3	Proto-Indo-European	stern-	forehead, chest, side

via Latin mastoīdēs

Step	Language	Word	Meaning
1	Latin	mastoīdēs	Shaped like a breast

Words derived from “sternocleidomastoīdēs”

sternocleidomastoid

Every word from Proto-Indo-European kleh₂u- →Every word from Proto-Hellenic klāwī́ds →Every word from Ancient Greek κλείς →