φρήν phrḗn

Meaning

the midrif (as a partition of the body), i.e. (figuratively and by implication, of sympathy) the feelings (or sensitive nature; by extension (also in the plural) the mind or cognitive faculties)

In the King James Version: understanding

Derivation: probably from an obsolete (to rein in or curb; compare G5420 (φράσσω));

Where it is used

• 1 Corinthians 14:20 Brothers, stop thinking like children. In regard to evil be infants, but in your thinking be mature.