4
conclusive(adjective, clear, strong, reasonable, easy)
4
earnest(adjective, sensible, true, steady, resolute)
4
exact(adjective, good, close, open, correct)
4
fiducial
4
guaranteed
4
harmless(adjective, clear, sound, gentle, pure)
4
honourable
4
indisputable(adjective, true, real, absolute, unequivocal)
4
persistent(adjective, strong, tough, honest, certain)
4
plausible(open, sound, reasonable, honest, sensible)
4
precise(adjective, good, close, open, correct)
4
punctilious(adjective, exact, careful, regular, honorable)
4
punctual(adjective, characteristic, time, quality, speed)
4
regular(adjective, firm, solid, exact, stable)
4
sturdy(adjective, calm, strong, secure, tough)
4
tenable(sound, reasonable, rational, realistic, authentic)
4
tested(adjective, flawless, infallible, proven, time-tested)
4
thorough(adjective, careful, resolute, meticulous, conscientious)
4
true-blue(adjective, close, open, correct, honest)
4
unbending(adjective, resolute, persistent, dedicated, unwavering)
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APASmart Define. (2016). reliable thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/reliable/thesaurus/synonyms
ChicagoSmart Define. 2016. "reliable thesaurus" https://smartdefine.org/reliable/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, reliable thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/reliable/thesaurus/synonyms>.
MLASmart Define. "reliable thesaurus" 3 March 2016. Web. 22 September 2026. <https://smartdefine.org/reliable/thesaurus/synonyms>