Synonyms and related words :
arbitrary, automated, automatic, automatous, autonomous, cybernated, discretional, discretionary, elective, free, free will, gratuitous, independent, nonmandatory, offered, optional, proffered, 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, spontaneous, unasked, unbesought, unbidden, uncalled-for, uncoerced, uncompelled, unforced, uninfluenced, uninvited, unpressured, unprompted, unrequested, unrequired, unsolicited, unsought, voluntary, volunteer, willful