10
bass(adjective, sound, intense, sounds, throaty)
10
difficult(adjective, hard, severe, meaning, abstract)
10
full(adjective, clear, strong, open, smooth)
10
inscrutable
10
insidious(adjective, smooth, sharp, cunning, tricky)
10
sincere(adjective, great, warm, energetic, enthusiastic)
10
subtle(adjective, quiet, delicate, complex, cunning)
10
thick(adjective, rough, large, fat, dense)
10
wise(adjective, characteristic, good, reasonable, keen)
9
abysmal(adjective, down, surface, extent, far)
9
cryptic(adjective, hard, evil, obscure, humble)
9
depth(noun, high, hole, hollow, gap)
9
hidden(adjective, hard, evil, obscure, complex)
9
impenetrable(adjective, set, obscure, solid, heavy)
9
incomprehensible
9
intimate(adjective, property, secret, private, personal)
9
knowing(adjective, sharp, smart, bright, intelligent)
9
learned(adjective, thoughtful, meaning, moral, knowledgeable)
9
sharp(adjective, strong, light, keen, smart)
9
wide(adjective, hard, down, thick, huge)
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APASmart Define. (2016). deep thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/deep/thesaurus/synonyms
ChicagoSmart Define. 2016. "deep thesaurus" https://smartdefine.org/deep/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, deep thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/deep/thesaurus/synonyms>.
MLASmart Define. "deep thesaurus" 24 March 2016. Web. 20 September 2026. <https://smartdefine.org/deep/thesaurus/synonyms>