7
headlong(adjective, adverb, prompt, violent, quick)
7
high-speed(adjective, direct, express, prompt, quick)
7
immobile(adjective, strong, secure, solid, intense)
7
in haste(expression, idiom, adverb, quickly, rapidly)
7
posthaste(adjective, adverb, early, speedy, quickly)
7
rooted(adjective, strong, secure, fixed, impassive)
7
stubborn(adjective, characteristic, quality, strong, secure)
6
bolted(adjective, strong, secure, short, substantial)
6
abruptly(adverb, quickly, rapidly, pronto)
6
intelligent(adjective, mind, quickness, possession, activity)
6
liege(adjective, continue, firm, honest, sensible)
6
lightweight
6
lively(adjective, keen, prompt, energetic, active)
6
locked(adjective, strong, sound, secure, firm)
6
ready(adjective, activity, prompt, quick, brisk)
6
stuck(adjective, firm, steady, fixed, tight)
6
unrestrained(adjective, open, light, free, restraint)
5
lewd(adjective, open, light, evil, informal)
5
precipitate(adjective, prompt, quick, abrupt, brisk)
5
promiscuous(adjective, informal, relaxed, wild, loose)
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APASmart Define. (2016). fast thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/fast/thesaurus/synonyms
ChicagoSmart Define. 2016. "fast thesaurus" https://smartdefine.org/fast/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, fast thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/fast/thesaurus/synonyms>.
MLASmart Define. "fast thesaurus" 1 April 2016. Web. 22 September 2026. <https://smartdefine.org/fast/thesaurus/synonyms>