Synonyms of 'extemporaneous'

ad-lib, ad lib, ad libitum, casual, extemporary, extempore, haphazard, hasty, impromptu, improvisatorial, improvise, improvised, impulsive, informal, jury-rigged, makeshift, off-the-cuff, offhand, precipitate, rough-and-ready, snap, spontaneous, stopgap, unhatched, unmade, unorganized, unplanned, unpremeditated, unprepared, unprimed, unready, unrehearsed, unstudied