flirty adj.

1550s, "to turn up one's nose, sneer at;" later "to rap or flick, as with the fingers" (1560s); "throw with a sudden movement," also "move in short, quick flights" (1580s). Perhaps imitative (compare flip (v.), also East Frisian flirt "a flick or light blow," flirtje "a giddy girl," which also might have fed into the English word), but perhaps rather from or influenced by flit (v.). Related: Flirted; flirting.

The main modern verbal sense of "play at courtship" (1777) probably developed from the noun (see flirt (n.)) but also could have grown naturally from the 16c. meaning "to flit inconstantly from object to object." To flirt a fan (1660s) was to snap it open or closed with a brisk jerk and was long considered part of the coquette's arsenal, which might have contributed to the sense shift. Or the word could have been influenced from French, where Old French fleureter meant "talk sweet nonsense," also "to touch a thing in passing," diminutive of fleur "flower" (n.) and metaphoric of bees skimming from flower to flower. French flirter "to flirt" is a 19c. borrowing from English.

adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy). Adjectives such as hugy, vasty are artificial words that exist for the sake of poetical metrics.