prep Antonyms

drift act spontaneously act without preparation do off the cuff do off the top of your head do something impromptu do something off the cuff do something off the top of one's head do something on the spur of the moment do something without special preparation do without preparation act according to the situation make it up as one goes along extemporize improvise go off at half-cock play it by ear ad lib extemporise fall into rush into busk it plunge in let things go as they may