late 14c., "fleeing, having fled, having taken flight," from Old French fugitif, fuitif "absent, missing," from Latin fugitivus "fleeing," past-participle adjective from stem of fugere "to flee, fly, take flight, run away; become a fugitive, leave the country, go into exile; pass quickly; vanish, disappear, perish; avoid, shun; escape the notice of, be unknown to," from PIE root *bheug- "to flee" (source also of Greek pheugein "to flee, escape, go into exile, be on the run," phyza "(wild) flight, panic," phyge "flight, exile;" Lithuanian būgstu, būgti "be frightened," bauginti "frighten someone," baugus "timid, nervous;" perhaps also Avestan būj(i)- "penance, atonement," būjat "frees"). Old English had flyma.
Meaning "lasting but a short time, fleeting" is from c. 1500. Hence its use in literature for short compositions written for passing occasions or purposes (1766).