Synonyms of extemporize in English:
extemporize
See US English definition of extemporize
See UK English definition of extemporize
See Spanish definition of improvisar
verb
1‘in modern jazz players extemporize in a very free manner’
SYNONYMS
improvise, ad lib, play it by ear, think on one's feet, cobble something together, throw something together, make it up as one goes along, take it as it comes
informal busk it, wing it, do something off the cuff, do something off the top of one's head, do something on the spur of the moment