Where does “phren” come from?

phren (English) comes from Ancient Greek φρήν, from Proto-Indo-European gʷʰren- — soul, mind; mind; an internal part of the body.

phren (English): The brain or mind; The diaphragm

Definitions

Step	Language	Word	Meaning
1	Ancient Greek	φρήν	The midriff, stomach and lower chest or breast;...
2	Proto-Indo-European	gʷʰren-	soul, mind; mind; an internal part of the body