Strong's #878: aphron (pronounced af'-rone)

from 1 (as a negative particle) and 5424; properly, mindless, i.e. stupid, (by implication) ignorant, (specially) egotistic, (practically) rash, or (morally) unbelieving:--fool(-ish), unwise.

Thayer's Greek Lexicon:

̓́

aphrōn

1) without reason

2) senseless, foolish, stupid

3) without reflection or intelligence, acting rashly

Part of Speech: adjective

Relation: from G1 (as a negative particle) and G5424

Citing in TDNT: 9:220, 1277

Usage:

This word is used 11 times:

 

Luke 11:40: " Ye fools, did not he that made that which is without make that which is within"
Luke 12:20: "God said unto him, Thou fool, this night thy soul"
Romans 2:20: "An instructor of the foolish, a teacher of babes, which hast the form of knowledge"
1 Corinthians 15:36: " Thou fool, that which thou sowest is not quickened, except it die:"
2 Corinthians 11:16: "think me a fool; if otherwise, yet as"
2 Corinthians 11:16: "if otherwise, yet as a fool receive me, that"
2 Corinthians 11:19: "For ye suffer fools gladly, seeing ye yourselves are wise."
2 Corinthians 12:6: "to glory, I shall not be a fool; for I will say the truth: but"
2 Corinthians 12:11: "I am become a fool in glorying; ye have compelled me: for I"
Ephesians 5:17: "Wherefore be ye not unwise, but understanding what"
1 Peter 2:15: "ye may put to silence the ignorance of foolish men:"