1. (p. pr. & vb. n.) of Fly.

2. (v. i.) Moving in the air with, or as with, wings; moving lightly or rapidly; intended for rapid movement.

aeronautics agile air service airborne airline ascending astronautics aviation axial back back-flowing backward ballooning blind flying breakneck brittle capricious changeable cloud-seeding commercial aviation contact flying corruptible cruising cursory dashing deciduous descending disappearing dissolving double-quick down-trending downward drifting dying eagle-winged ephemeral evanescent evaporating expeditious express fading fast festinate feverish fickle fleet fleeting flight flitting flowing fluent fluttering fly-by-night fragile frail fugacious fugitive furious galloping general aviation gliding going gyrational gyratory hair-trigger hasty headlong hovering hurried hustling immediate impermanent impetuous impulsive inconstant instant insubstantial jet-propelled last-minute light of heel light-footed lively melting mercurial momentary mortal mounting mutable nimble nimble-footed nondurable nonpermanent on the spot passing perishable pilotage plunging precipitate progressive prompt quick quick as lightning quick as thought rapid reckless reflowing refluent regressive retrogressive rising rocket-propelled rotary rotational rotatory running rushing sailing sailplaning short-lived sideward sinking slap-bang slapdash snap snappy soaring spanking speedy streaming superficial swift temporal temporary transient transitive transitory undurable unenduring unstable up-trending upward urgent vanishing volant volatile volitant winged winging