1
suasive
1
suitable(adjective, friendly, happy, sympathetic, useful)
1
supreme(main, chief, independent, principal, prevailing)
1
systematic(tough, energetic, effective, adept, effectual)
1
timely(adjective, friendly, happy, sympathetic, useful)
1
true(sound, reasonable, rational)
1
trustworthy(good, sound, right, reasonable, rational)
1
upper hand(expression, strong, energetic, vigorous, capable)
1
well-organized(tough, energetic, effective, adept, effectual)
1
wicked(strong, energetic, vigorous, capable, effective)
1
worthwhile
0
abler
0
ablest
0
accessible(useful, beneficial, advantageous)
0
accidental(adjective, happy, beneficial, fortunate, opportune)
0
accommodating(useful, beneficial, advantageous)
0
accomplished(tough, effective, adept, effectual, well-organized)
0
acting
0
acute(sensible, wise, shrewd)
0
adapted(tough, energetic, effective, adept, effectual)
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APASmart Define. (2015). efficacious thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/efficacious/thesaurus/synonyms
ChicagoSmart Define. 2015. "efficacious thesaurus" https://smartdefine.org/efficacious/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, efficacious thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/efficacious/thesaurus/synonyms>.
MLASmart Define. "efficacious thesaurus" 13 October 2015. Web. 22 September 2026. <https://smartdefine.org/efficacious/thesaurus/synonyms>