Where does “オトガイ舌筋” come from?

オトガイ舌筋 (Japanese) comes from Japanese 舌筋, from Japanese 舌, from Old Japanese した, from Translingual − — A long signal, used to form Morse code text, together with. (a short signal).

オトガイ舌筋 (Japanese): a genioglossus muscle

Definitions

a genioglossus muscle

Ancestry of “オトガイ舌筋”, step by step

オトガイ舌筋 traces back through two separate lines of ancestry.

via Japanese 舌筋

Step	Language	Word	Meaning
1	Japanese	舌筋	a tongue muscle
2	Japanese	舌	tongue
3	Old Japanese	した	—
4	Translingual	−	A long signal, used to form Morse code text, together with. (a short signal)

via Japanese 頤

Step	Language	Word	Meaning
1	Japanese	頤	—

Every word from Translingual − →Every word from Old Japanese した →Every word from Japanese 舌 →