הֶבֶל hebel (H1892)

emptiness or vanity; figuratively, something transitory and unsatisfactory; often used as an adverb

n m 1) vapour, breath 1a) breath, vapour 1b) vanity (fig.) adv 2) vainly

or (rarely in the abs.) הֲבֵל; from הָבַל (H1891);