8
tundra(noun, flat, land, prairie, lowland)
8
unadulterated(adjective, simple, clean, pure, true)
8
unaesthetic(adjective, appearance, ugly, unattractive, aroused negative)
8
unremarkable(adjective, good, simple, common, ordinary)
7
average(adjective, good, mean, simple, reasonable)
7
blatant(adjective, clear, open, flat, total)
7
bluff(adjective, open, honest, straightforward, blunt)
7
certain(adjective, clear, flat, firm, honest)
7
coherent(adjective, clear, simple, sharp, rational)
7
crystal clear(expression, adjective, clear, see, exact)
7
frugal(adjective, quality, slight, thin, delicate)
7
fundamental(adjective, simple, pure, straightforward, basic)
7
gross(adjective, clear, flat, total, awful)
7
moor(noun, flat, land, prairie, lowland)
7
perfect(adjective, simple, right, clean, big)
7
pronounced(adjective, clear, see, sharp, bright)
7
rude(adjective, poor, straightforward, blunt, incomplete)
7
self-evident(adjective, obvious)
7
unobtrusive(adjective, calm, quiet, simple, soft)
7
unquestionable(adjective, right, sharp, flat, true)
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APASmart Define. (2016). plain thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/plain/thesaurus/synonyms
ChicagoSmart Define. 2016. "plain thesaurus" https://smartdefine.org/plain/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, plain thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/plain/thesaurus/synonyms>.
MLASmart Define. "plain thesaurus" 31 March 2016. Web. 20 September 2026. <https://smartdefine.org/plain/thesaurus/synonyms>