ex·tem·po·rize extemporizes extemporizing extemporized in BRIT, also use extemporise If you extemporize, you speak, act, or perform something immediately, without rehearsing or preparing it beforehand. He completely departed from the text and extemporized in a very energetic fashion. = improvise. to speak or perform without preparation or practice
To do, make, or utter extempore or off-hand; to prepare in great haste, under urgent necessity, or with scanty or unsuitable materials; as, to extemporize a dinner, a costume, etc