12
intent(adjective, strong, flat, intense, certain)
12
single-minded(adjective, keen, firm, sensible, solid)
12
tough(adjective, calm, clear, strong, severe)
11
dead in the water
11
indomitable(adjective, strong, determined, vigorous, noble)
11
pertinacious(adjective, tough, firm, determined, resolute)
11
stalwart(adjective, calm, strong, tough, keen)
10
diligent(adjective, resolute, persevering, tenacious)
10
insistent(adjective, determined, resolute, obstinate, uncompromising)
10
intransigent(adjective, determined, resolute, obstinate, stubborn)
10
trustworthy(adjective, good, close, strong, correct)
10
trusty(adjective, good, close, strong, correct)
10
undaunted(adjective, bold, brave, tenacious)
10
unfailing(adjective, good, strong, honest, solid)
10
untiring
9
brave(adjective, clear, tough, severe, determined)
9
decided(adjective, firm, intense, certain, deliberate)
9
definite(adjective, good, strong, complete, easy)
9
secure(verb, adjective, calm, strong, firm)
9
stern(adjective, firm, resolute, persistent, rigid)
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APASmart Define. (2016). steadfast thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/steadfast/thesaurus/synonyms
ChicagoSmart Define. 2016. "steadfast thesaurus" https://smartdefine.org/steadfast/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, steadfast thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/steadfast/thesaurus/synonyms>.
MLASmart Define. "steadfast thesaurus" 11 March 2016. Web. 21 September 2026. <https://smartdefine.org/steadfast/thesaurus/synonyms>