Strong's G3912 · Greek

παραφρονέω

paraphroneo · par-af-ron-eh'-o

from 3844 and 5426; to misthink, i.e. be insane (silly)

Scholarly Lexicons

Abbott-Smith Manual Greek Lexicon

 1 παρα-φρονέω ( παρά , φρήν ), [in LXX: Za 7:11 ( סרר )*;] to be beside oneself , be deranged : II Co 11:23 .† 

G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain