Synonyms for Impulsive:

adj.

adventurous (adjective)
daring.
all (adjective)
unprompted.
capricious (adjective)
frivolous, arbitrary, fitful, indecisive, sporadic, wayward, fly-by-night, scatterbrained, flighty, capricious, mutable, vacillating, fleeting, whimsical, volatile, changeable, random, fanciful, fluctuating, Flitting, erratic, fickle.
changeable (adjective)
inconstant, Permutable.
excitable (adjective)
excitable, brittle, cranky, quick-tempered, edgy, tempestuous, short-tempered, explosive, crusty, passionate, volcanic, nervous, irritable, combustible, stormy, high-strung, fragile, ardent, reckless, sensitive, touchy, hot-tempered, volatile, rash, emotional, fiery.
fickle (adjective)
plastic, pliant, fluctuating, flighty, fickle, indecisive, unreliable, changeable, inconstant, Permutable, undependable, modifiable, pliable, volatile, mutable, malleable.
foolish (adjective)
unthinking.
headlong (adjective)
headlong.
impulsive (adjective)
spontaneous, abrupt, hasty, instantaneous, reflexive, extemporaneous, unrehearsed, improvised, rash, ill-considered, unpremeditated, impromptu.
irresolute (adjective)
irresponsible, inconsistent, shrinking, ambivalent, infirm, volatile, changeable, halfhearted, yellow, fickle, uncertain, insipid, spineless, unresolved, undependable, shifty, shy, capricious, double-minded, Flitting, erratic, undecided, indecisive, weak, unwilling, vacillating, Shilly-shally, irresolute, dillydallying, tentative, fly-by-night, hesitant, unsure, watery.
motiveless (adjective)
capricious, fleeting, Systemless, rambling, irregular, random, indecisive, wandering, haphazard, volatile, unmethodical, careless, sporadic, Flitting, fickle, reasonless, motiveless, spastic, adrift, whimsical, arbitrary, nonsystematic, ambivalent, chancy, fanciful, flighty, wayward.
rash (adjective)
brazen, desperado, audacious, unheedful, irresponsible, daring, thoughtless, daredevil, injudicious, foolhardy, breakneck, precipitant, incautious, reckless, rash, hectic, careless, impetuous, brash, unconsidered, hotheaded, imprudent.
tending to act without thought (adjective)
headlong, extemporaneous, spontaneous, impetuous, unpremeditated, emotional, unpredictable, rash, careless, passionate, sudden, precipitate, hasty, unconsidered, unprompted, abrupt, offhand.

n.

improvident, mindless, precipitant, temerarious, careful, harum-scarum, unthinking, foolish, slapdash, unconsidered, headlong, precipitate, undiscriminating, shallow. impetuous (noun)
sudden, unpredictable.
impulsive (noun)
dynamic, hotheaded, tearaway, spontaneous, self-generated, unpremeditated, impetuous, madcap, arbitrary, incautious, unprompted, capricious, dynamical, whimsical, driving, brainish.
spontaneous (noun)
offhand, spur-of-the-moment.

Other synonyms:

shallow, undiscriminating, precipitant, mindless, temerarious, unconsidered. foolish, harum-scarum, reflex, headlong, precipitate. improvident. slapdash.

Usage examples for impulsive

  1. Her mother had been an amiable woman, of the poetical temperament nevertheless, too enthusiastic, imaginative, impulsive for the repose of a sober scholar; an admirable woman, still, as you see, a woman, a fire- work. – The Complete Project Gutenberg Works of George Meredith by George Meredith
  2. Then he felt an impulsive pressure as she looked up at him. – The Last Shot by Frederick Palmer
  3. I did not know that he could be so impulsive – The Idol of Paris by Sarah Bernhardt