(a.) Left to discretion; unrestrained except by discretion or judgment; as, an ambassador with discretionary powers.

arbitrary autonomous discretional elective free free will gratuitous independent nonmandatory offered optional proffered self-acting self-active self-determined self-determining spontaneous unasked unbesought unbidden uncalled-for uncoerced uncompelled unforced uninfluenced uninvited unpressured unprompted unrequested unrequired unsolicited unsought voluntary volunteer willful