Limitless Word
ματαιόωmataióō
GreekG31541 occurrences (KJV)

to render (passively, become) foolish, i.e. (morally) wicked or (specially), idolatrous

KJV renders it: become vain

Where it appears

  • Rom 1:21Because, knowing God, they didn’t glorify him as God, neither gave thanks, but became vain in their reasoning, and their senseless heart was darkened.

Lexical data: Strong’s Hebrew & Greek Dictionaries (1890, public domain; openscriptures, CC-BY-SA). Word tagging from the Strong’s-numbered KJV.