1. (a.) Inclined to act on transient feelings; unpremeditated\.

2. (a.) Having the power of driving or impelling; giving an impulse; moving; impellent.

3. (a.) Acting momentarily, or by impulse; not continuous; -- said of forces.

4. (n.) That which impels or gives an impulse; an impelling agent.

a bit previous abrupt actuating adrift advanced afloat alternating amorphous animating automatic blind breakneck breathless brittle capricious causal causative changeable changeful changing choppy compelling compulsive conditioned corruptible deciduous desultory deviable deviating deviative deviatory devil-may-care different directive disorderly divaricate divergent diversified diversiform dizzy driving dying eccentric electrifying emotional ephemeral erose erratic evanescent extemporaneous fading far ahead fast and loose fickle fitful fleeting flickering flighty flitting fluctuating fly-by-night flying foolhardy forced forward fragile frail freakish fugacious fugitive giddy half-baked half-cocked hasty headlong ill-considered immediate impatient impellent impelling impermanent impetuous inconsistent inconstant indecisive inducive infirm inherent innate instinctive insubstantial involuntary irregular irresolute irresponsible jagged jerky libidinal madcap mazy mechanical mercurial momentary moody mortal motivating motivational motive motley moving mutable natural nerve-shattering nonconformist nondurable nonpermanent nonstandard nonuniform not firm offhand overhasty oversoon panting passing perishable pluralistic precipitant precipitate precipitous precocious premature pressing previous pulsive quick ragged rambling rash reckless reflex reflexive restless rough roving rushed scatterbrained shapeless shifting shifty shocking short-lived shuffling snap spasmodic speedy spineless spontaneous sporadic spur-of-the-moment startling subliminal sudden surprising swift temporal temporary thrusting too early too soon transient transitive transitory unaccountable unanticipated uncertain unconscious unconsidered uncontrolled uncrystallized undependable undisciplined undurable unenduring unequable unequal uneven unexpected unfixed unforeseen unintentional unjelled unlearned unlooked-for unmatured unmeditated unorthodox unplanned unpredictable unpredicted unpremeditated unprepared unprompted unreliable unrestrained unripe unsettled unstable unstable as water unstaid unsteadfast unsteady unsystematic unthinking untimely ununiform unwilled unwilling unwitting urgent vacillating vagrant variable variegated variform various varying vicissitudinary vicissitudinous volatile wandering wanton wavering wavery wavy wayward whimsical wild wishy-washy