5
presto(hot, quick, nimble, speedy, brisk)
5
rapid(adjective, adverb, hot, fast, quick)
5
speedy(adjective, adverb, hot, fast, quick)
4
breakneck(adjective, adverb, hot, fast, quick)
4
expeditiously(adverb, quick, early, immediately, quickly)
4
immediately(adverb, quickly, rapidly, haste, speedily)
4
in haste(expression, idiom, quickly, rapidly, haste)
4
snappily(soon, swiftly)
3
amain
3
briskly(adverb, quickly, rapidly, speedily)
3
chop-chop(hot, quick, nimble, speedy, brisk)
3
headlong(adjective, adverb, fast, rapid, swift)
3
hurriedly(adverb, quick, quickly, rapidly, soon)
3
instantaneously(adverb, velocity, haste)
3
on the double(expression, idiom, hot, fast, quick)
3
suddenly
2
abruptly
2
at once(expression, adjective, idiom, adverb, fast)
2
by cable(expression, idiom, haste)
2
by express(expression, idiom, haste)
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APASmart Define. (2015). posthaste thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/posthaste/thesaurus/synonyms
ChicagoSmart Define. 2015. "posthaste thesaurus" https://smartdefine.org/posthaste/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, posthaste thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/posthaste/thesaurus/synonyms>.
MLASmart Define. "posthaste thesaurus" 13 April 2015. Web. 23 September 2026. <https://smartdefine.org/posthaste/thesaurus/synonyms>