With little or no preparation or forethought. Synonyms: ad-lib, extemporaneous, extempore, impromptu, off-the-cuff, offhand, offhanded, unrehearsed. "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"
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