Extemporize

глагол то же, что и extemporise импровизировать Синоним(ы): improvise

Большой англо-русский словарь

Extemporize

verb (-rized; -rizing) intransitive verb 1. to do something extemporaneously; improvise; especially to speak extemporaneously 2. to get along in a makeshift manner transitive verb to compose, perform, or utter extemporaneously; improvise Example: extemporized an after-dinner speechextemporizer noun

Энциклопедический словарь Мерриама-Вебстера