Word Origin
denominative verb from hebel
Definition
to act emptily, become vain
NASB Word Usage
act foolishly (1), became empty (1), became vain (1), leading you into futility (1), vainly hope (1).

וַיֶּהְבָּ֔לוּ וַיֶּהְבָּֽלוּ׃ ויהבלו ויהבלו׃ מַהְבִּלִ֥ים מהבלים תֶּ֫הְבָּ֥לוּ תֶּהְבָּֽלוּ׃ תהבלו תהבלו׃ mah·bi·lîm mahbiLim mahbilîm teh·bā·lū tehBalu tehbālū vaiyehBalu way·yeh·bā·lū wayyehbālūInterlinear Greek • Interlinear Hebrew • Strong's Numbers • Englishman's Greek Concordance • Englishman's Hebrew Concordance • Parallel Texts