THESAURUS
arbitrary, automatic, autonomous, discretional, discretionary, elective, free, free will, gratuitous, impulsive, independent, instinctive, involuntary, nonmandatory, offered, optional, proffered, self-acting, self-active, self-determined, self-determining, spontaneous, unasked, unbesought, unbidden, uncalled-for, uncoerced, uncompelled, unconscious, undesigned, unforced, unguarded, unguided, uninfluenced, unintended, unintentional, uninvited, unmeant, unmeditated, unplanned, unpremeditated, unpressured, unpurposed, unrequested, unrequired, unsolicited, unsought, unthinking, unthought-of, unwitting, voluntary, volunteer, willful
ROGET THESAURUS
Impulse
N
impulse, sudden thought, impromptu, improvisation, inspiration, flash, spurt, improvisatore, creature of impulse, extemporaneous, impulsive, indeliberate, snap, improvised, improvisate, improvisatory, unpremeditated, unmeditated, improvise,
unprompted, unguided, natural, unguarded, spontaneous, instinctive, extempore, extemporaneously, offhand, impromptu, a limproviste, improviso, on the spur of the moment, on the spur of the occasion, impulse, impulsion, impetus, momentum, push, pulsion, thrust, shove, jog, jolt, brunt, booming, boost, throw, explosion, propulsion, percussion, concussion, collision, occursion, clash, encounter, cannon, carambole, appulse, shock, crash, bump, impact, elan, charge, beating, blow, dint, stroke, knock, tap, rap, slap, smack, pat, dab, fillip, slam, bang, hit, whack, thwack, cuff, squash, dowse, swap, whap, punch, thump, pelt, kick, punce, calcitration, ruade, arietation, cut, thrust, lunge, yerk, carom, carrom, clip, jab, plug, sidewinder, sidewipe, sideswipe, hammer, sledge hammer, mall, maul, mallet, flail, ram, rammer, battering ram, monkey, pile-driving engine, punch, bat, cant hook, cudgel, ax, dynamics, seismometer, accelerometer, earthquake detector, impelling, impulsive, impellent, booming, dynamic, dynamical, impelled, a hit, a very palpable hit.
