13
offhand(adjective, free, casual, impulsive, prepared)
12
extemporaneous(adjective, free, casual, impulsive, prepared)
12
extempore(adjective, free, casual, impulsive, prepared)
12
impromptu(adjective, free, casual, impulsive, prepared)
8
off-the-cuff(adjective, informal, prepared, spontaneous, unprepared)
7
ad-lib(adjective, free, fake, casual, prepared)
7
improvised(adjective, free, casual, impulsive, prepared)
7
offhanded
7
unrehearsed(adjective, free, casual, impulsive, prepared)
6
unpremeditated(adjective, free, casual, impulsive, spontaneous)
6
unprepared(adjective, free, casual, impulsive, spontaneous)
6
unstudied(adjective, free, casual, impulsive, spontaneous)
5
spur-of-the-moment(adjective, free, casual, impulsive, prepared)
4
ad lib(expression, adjective, free, casual, spontaneous)
4
spontaneous(adjective, free, casual, impulsive, unprepared)
3
unplanned(adjective, free, casual, impulsive, spontaneous)
2
automatic(adjective, free, casual, impulsive, spontaneous)
2
extemporal(adjective, unrehearsed, extemporaneous)
2
makeshift(adjective, free, casual, impulsive, spontaneous)
2
off the cuff(expression, adjective, free, impromptu, improvised)
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APASmart Define. (2015). extemporary thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/extemporary/thesaurus/synonyms
ChicagoSmart Define. 2015. "extemporary thesaurus" https://smartdefine.org/extemporary/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, extemporary thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/extemporary/thesaurus/synonyms>.
MLASmart Define. "extemporary thesaurus" 14 April 2015. Web. 20 September 2026. <https://smartdefine.org/extemporary/thesaurus/synonyms>