6
giant(adjective, great, big, large, huge)
6
hefty(adjective, great, big, substantial, large)
6
humongous(adjective, great, big, large, huge)
6
important(adjective, significant, substantial, large, valuable)
6
large-scale(adjective, big, substantial, large, grand)
6
lengthy(adjective, great, big, deep, high)
6
monstrous(adjective, huge, vast, immense, massive)
6
sizeable(adjective, significant, substantial, large)
5
detailed(adjective, great, fancy, top, perfect)
5
Brobdingnagian(adjective, huge, vast, massive)
5
across-the-board(adjective, complete, full, grand, broad)
5
cosmopolitan(adjective, union, universal, worldwide, versatile)
5
deep(adjective, open, great, spread, full)
5
encyclopaedic
5
far-flung(adjective, big, large, grand, huge)
5
generous(adjective, open, great, top, substantial)
5
grand(adjective, strong, great, big, powerful)
5
in-depth(adjective, complete, total, thorough, unrestrained)
5
indiscriminate(adjective, big, large, grand, huge)
5
infinite(open, complete, full, space, large)
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APASmart Define. (2016). extensive thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/extensive/thesaurus/synonyms
ChicagoSmart Define. 2016. "extensive thesaurus" https://smartdefine.org/extensive/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, extensive thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/extensive/thesaurus/synonyms>.
MLASmart Define. "extensive thesaurus" 29 March 2016. Web. 21 September 2026. <https://smartdefine.org/extensive/thesaurus/synonyms>