Where does “iasc” come from?

iasc (Irish) comes from Old Irish íasc, from Proto-Celtic *ɸeiskos, from Proto-Indo-European *peysk-.

iasc (Irish): fish; to fish

Definitions

Step	Language	Word	Meaning
1	Old Irish	íasc	fish
2	Proto-Celtic	*ɸeiskos	—
3	Proto-Indo-European	*peysk-	—

iasc — Etymology, Origin & Word History | Etymology Explorer