5
quiet(adjective, calm, dull, secure, soft)
5
sensible(adjective, sound, reasonable, moderate, firm)
5
smooth(adjective, calm, quiet, direct, right)
5
still(adjective, calm, dull, quiet, secure)
5
sty(noun, abode, uncleanness)
5
systematic(adjective, calm, smooth, steady, temperate)
5
tenacious(adjective, strong, sound, secure, tough)
5
unbroken(adjective, calm, quiet, direct, smooth)
5
undeviating(adjective, quiet, strong, direct, smooth)
5
unruffled(adjective, calm, quiet, smooth, soft)
5
unswerving(adjective, firm, solid, fixed, resolute)
5
unvaried
5
vigorous(adjective, strong, sound, complete, tough)
5
well-founded(adjective, strong, sound, secure, tough)
4
accountable
4
chronic(adjective, persistent, continuous, endless, relentless)
4
continuing(adjective, fixed, unaffected, lasting, permanent)
4
controlled(adjective, reasonable, moderate, restrained, cautious)
4
cool(adjective, calm, quiet, sound, reasonable)
4
cowshed
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APASmart Define. (2015). stable thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/stable/thesaurus/synonyms
ChicagoSmart Define. 2015. "stable thesaurus" https://smartdefine.org/stable/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, stable thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/stable/thesaurus/synonyms>.
MLASmart Define. "stable thesaurus" 10 April 2015. Web. 22 September 2026. <https://smartdefine.org/stable/thesaurus/synonyms>