Where does “レプンカムィ” come from?

レプンカムィ (Ainu) comes from Ainu レㇷ゚, from Ainu レ — three.

レプンカムィ (Ainu): orca

Definitions

Step	Language	Word	Meaning
1	Ainu	レㇷ゚	three, three things
2	Ainu	レ	three

レプンカムィ — Etymology, Origin & Word History | Etymology Explorer