7
set(adjective, activity, solid, intense, heavy)
6
ample(adjective, open, spread, enthusiastic, loose)
6
bright(adjective, characteristic, good, strong, light)
6
sly(adjective, smooth, sharp, cunning, clever)
6
abysm(noun, high)
6
abyssal(adjective, down, far, unfathomable)
6
below(adjective, position, down, far, low-set)
6
considerable(adjective, important, significant, vital, greatness)
6
dense(adjective, set, solid, dark, heavy)
6
engrossed(adjective, set, keen, full, fixed)
6
erudite(adjective, rational, thoughtful, moral, knowledgeable)
6
essential(adjective, original, basic, intimate, secret)
6
extended(adjective, open, full, large, extensive)
6
fast(adjective, property)
6
fathomless(adjective, down, far, low-set, low-lying)
6
fixed(adjective, activity, set, solid, intense)
6
in-depth(adjective, intimate, secret, private, demanding)
6
interior(noun, adjective, hold, intimate, secret)
6
internal(adjective, intimate, secret, private, personal)
6
intriguing(adjective, cunning, devious, scheming)
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APASmart Define. (2016). deep thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/deep/thesaurus/synonyms
ChicagoSmart Define. 2016. "deep thesaurus" https://smartdefine.org/deep/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, deep thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/deep/thesaurus/synonyms>.
MLASmart Define. "deep thesaurus" 24 March 2016. Web. 21 September 2026. <https://smartdefine.org/deep/thesaurus/synonyms>