2
by telegraph(expression, idiom, haste)
2
directly(adjective, adverb, fast)
2
early(rapidly, haste, soon, swiftly, instantly)
2
expeditive(hot, fast, quick, nimble, speedy)
2
express(fast, quick, rapid, speedy, swift)
2
flat out(adverb, informal, fast)
2
in double time(expression, idiom, soon, swiftly, snappily)
2
in high gear(expression, idiom, soon, swiftly, snappily)
2
in nothing flat(expression, idiom, adverb, hot, fast)
2
in short order(expression, idiom, early, quickly, rapidly)
2
lickety split(expression, adjective, adverb, hot, quick)
2
like a bat out of hell(expression, idiom, adverb, hot, fast)
2
like a shot(expression, idiom, adverb, fast, immediately)
2
pell-mell(adjective, adverb, fast, carelessly, hurriedly)
2
straightaway(adjective, adverb, fast)
2
trippingly
2
with all haste(expression, idiom, haste)
2
with speed(expression, idiom, velocity)
1
ASAP(fast, rapid, swift)
1
PDQ(hot, quick, rapid, nimble, speedy)
11 years ago|2.9k views|share |citing 
APASmart Define. (2015). posthaste thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/posthaste/thesaurus/synonyms
ChicagoSmart Define. 2015. "posthaste thesaurus" https://smartdefine.org/posthaste/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, posthaste thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/posthaste/thesaurus/synonyms>.
MLASmart Define. "posthaste thesaurus" 13 April 2015. Web. 24 September 2026. <https://smartdefine.org/posthaste/thesaurus/synonyms>