215 entries under adjective topic. ×

8
unvarying(calm, strong, secure, firm)
7
interminable(steady, persistent, constant, continuous)
7
dateless(steady, constant, continuous, lasting)
7
incessant(steady, stable, persistent, constant)
7
infinite(continuous, endless, boundless, everlasting)
7
perdurable(calm, strong, continue, sturdy)
6
ageless(fixed, lasting, unchanging, unchangeable)
6
indelible(firm, true, fixed, constant)
6
inveterate(impulse, established)
6
irreversible
6
irrevocable(fixed, unchangeable)
6
long-term(vast, lasting, lifelong, diurnal)
6
never-ending(constant, continuous, endless, infinite)
6
regular(usual, steady, stable, routine)
6
sempiternal
6
uninterrupted(steady, stable, regular, fixed)
6
unremitting(steady, stable, persistent, constant)
5
solid(calm, strong, secure, steady)
5
unfading(fixed, constant, vast, enduring)
5
unrelenting(persistent, constant, continuous, endless)
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APASmart Define. (2016). permanent thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/permanent/thesaurus/synonyms
ChicagoSmart Define. 2016. "permanent thesaurus" https://smartdefine.org/permanent/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, permanent thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/permanent/thesaurus/synonyms>.
MLASmart Define. "permanent thesaurus" 26 February 2016. Web. 21 September 2026. <https://smartdefine.org/permanent/thesaurus/synonyms>