extemporize

verb

1. (intransitive)To perform or speak without prior planning or thought; to act in an impromptu manner; to improvise.

   “"Will you please tell me whose music you have been playing?" . . . "It's nobody's, miss." "Do you mean you have been extemporizing all this time?"”

   “But while some of his predecessors liked to extemporize, Obama prefers the message to be just so.”

2. (transitive)To adapt, improvise, or devise action or speech in an impromptu or spontaneous manner.

   “As the music came fresher on their ears, they danced to its cadence, extemporizing new steps and attitudes.”

   “The small jelly-speck, which we call the amoeba, has no organs save what it can extemporize as occasion arises.”

   “The wine runs into pitchers, washing-basins, shards, chamber- vessels, and other extemporized receptacles.”

   “His most famous words — "I have a dream" — were extemporized.”

   “The evidence of my eyes does not lead me to the conclusion that Woody Brown is communicating via a letter board. It leads me to the conclusion that he is randomly tapping the board and that his mother is extemporizing, whether consciously or not.”