intransitive verb. To do or perform (something) without prior preparation or practice.

intransitive verb. To perform an act or utter something in an impromptu manner; improvise.

To make or provide for a sudden and unexpected occasion; prepare in haste with the means within one's reach: as, to extemporize a speech or a dinner; to extemporize a couch or a shelter.

Specifically To compose without premeditation on a special occasion: as, he extemporized a brilliant accompaniment.

To speak extempore; speak without previous study or preparation; discourse without notes or written draft.

To sing, or play on an instrument, composing the music as it proceeds; improvise. See improvise.

Also spelled extemporise.

intransitive verb. To speak extempore; especially, to discourse without special preparation; to make an offhand address.

transitive verb. To do, make, or utter extempore or off-hand; to prepare in great haste, under urgent necessity, or with scanty or unsuitable materials

verb. To do something, particularly to perform or speak, without prior planning or thought; to act in an impromptu manner; to improvise.

verb. To do, create, improvise, adapt, or devise in an impromptu or spontaneous manner.

verb. perform without preparation

verb. manage in a makeshift way; do with whatever is at hand

"You really have to know the melody inside out and that allows you to embellish, to extemporize on it with freedom."

extemporizing-machine  off the cuff  off the top of one's head  play it by ear  

extemporaneous  extempore  extemporisation  extemporization  

extemporized  extemporizing  

contend  cope  deal  do  execute  

ad-lib  be caught napping  be surprised  be taken unawares  be unprepared  

extemporized  extemporizes  extemporizing