The term 'extemporizes' means to speak or act without preparation. The crossword solutions for this term are 'VAMPS' (5 letters), 'adlibs' (6 letters) and 'fakesit' (7 letters). VAMPS are short musical passages that are repeated in order to extend a song, adlibs are spontaneous remarks made during a performance, and fakesit is a slang term for improvising. All of these terms refer to the act of extemporizing.