Synonyms and related words :
ad lib, arbitrary, automated, automatic, automatous, autonomous, bat, baton, billy, billy club, bludgeon, casual, club, cybernated, discretional, discretionary, elective, extemporaneous, extempore, free, free will, gratuitous, gut, ill-advised, ill-considered, ill-devised, immediate, impetuous, impromptu, improvised, impulsive, inadvertent, indeliberate, independent, inherent, innate, instinctive, instinctual, involuntary, libidinal, mace, mechanical, natural, nightstick, nonmandatory, off the cuff, offered, offhand, optional, proffered, reflex, reflexive, self-acting, self-active, self-adjusting, self-closing, self-controlled, self-cooking, self-determined, self-determining, self-directed, self-directing, self-dumping, self-governed, self-governing, self-lighting, self-operative, self-regulative, self-starting, self-winding, self-working, semiautomatic, simple, snap, spontoon, spur-of-the-moment, subliminal, truncheon, unadvised, unannounced, unasked, unbesought, unbidden, uncalculated, uncalled-for, uncoerced, uncompelled, unconscious, unconsidered, unconstrained, undeliberate, undeliberated, undesigned, unforced, unguarded, uninfluenced, unintended, unintentional, uninvited, unlearned, unmeditated, unplanned, unpremeditated, unprepared, unpressured, unprompted, unrehearsed, unrequested, unrequired, unsolicited, unsophisticated, unsought, unstudied, unthinking, unwilled, unwitting, voluntary, volunteer, willful