2
long-term(adjective, permanent, lifelong)
2
mammoth(adjective, huge, vast, immense, massive)
2
massive(adjective, huge, vast, immense, infinite)
2
monolithic(adjective, continuous)
2
monumental(adjective, huge, vast, immense, massive)
2
myriad(adjective, innumerable)
2
never-ceasing(continuous, everlasting, uninterrupted, eternal, undying)
2
never-failing
2
no holds barred(expression, adjective, idiom, immense, infinite)
2
over-long
2
perdurable(continuous, permanent, unlimited, everlasting, eternal)
2
persisting(adjective, determined, steady, stable, persistent)
2
ponderous(adjective, wordy)
2
prodigious(adjective, huge, vast, immense, massive)
2
progressive
2
repetitious(adjective, continuous, everlasting, uninterrupted, recurring)
2
stupendous(adjective, huge, vast, massive, unlimited)
2
sumless
2
sustained(adjective, persistent, constant, continuous, relentless)
2
tremendous(adjective, great, big, huge, vast)
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APASmart Define. (2016). endless thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/endless/thesaurus/synonyms
ChicagoSmart Define. 2016. "endless thesaurus" https://smartdefine.org/endless/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, endless thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/endless/thesaurus/synonyms>.
MLASmart Define. "endless thesaurus" 26 February 2016. Web. 22 September 2026. <https://smartdefine.org/endless/thesaurus/synonyms>