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"
[ ik-'stem-p&-(")rE ] (adverb or adjective.) 1553. From Latin ex (“immediately after”) + tempore, ablative singular of tempus (“time", "opportunity", "occasion”)