Where does “caint” come from?

caint (Irish) comes from Brythonic Cantio, from Proto-Celtic kantos, from Proto-Indo-European *kh₂ndʰ-.

caint (Irish): speech; talking

Definitions

Step	Language	Word	Meaning
1	Brythonic	Cantio	—
2	Proto-Celtic	kantos	corner; rim
3	Proto-Indo-European	*kh₂ndʰ-	—

caint — Etymology, Origin & Word History | Etymology Explorer