v. To compose, recite, or sing extemporaneously, especially in verse; to extemporize; also, to play upon an instrument, or to act, extemporaneously.v. To bring about, arrange, do, or make, immediately or on short notice, without previous preparation and with no known precedent as a guide.v. To invent, or provide, offhand, or on the spur of the moment.verb-intransitive. To produce or render extemporaneous compositions, especially in verse or in music, without previous preparation; hence, to do anything offhand.