Adjective extemporaneous has 1 sense
- ad-lib, extemporaneous, extemporary, extempore, impromptu, offhand, offhanded, off-the-cuff, unrehearsed - with little or no preparation or forethought; "his ad-lib comments showed poor judgment"; "an extemporaneous piano recital"; "an extemporary lecture"; "an extempore skit"; "an impromptu speech"; "offhand excuses"; "trying to sound offhanded and reassuring"; "an off-the-cuff toast"; "a few unrehearsed comments"
Antonym: prepared (indirect, via unprepared)
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