11
well-defined(adjective, clear, sharp, exact, straightforward)
10
genuine(adjective, good, open, simple, right)
10
homespun(adjective, dull, simple, ordinary, usual)
10
steppe(noun, flat, plain, field, land)
10
unconcealed(adjective, clear, open, direct, free)
10
undisguised(adjective, good, clear, open, free)
10
undistinguished(adjective, good, simple, ordinary, familiar)
10
unsightly(adjective, appearance, awful, ugly, revolting)
9
clean(adjective, clear, simple, easy, sharp)
9
familiar(adjective, dull, open, free, simple)
9
hideous(adjective, appearance, awful, common, usual)
9
perceivable(adjective, clear, substantial, obvious, visible)
9
prosaic(adjective, dull, mean, simple, tough)
9
spartan(adjective, simple, clean, pure, natural)
9
uncomely(adjective, appearance, awful, beautiful, revolting)
9
unexceptional(adjective, good, simple, reasonable, common)
9
unornamented(adjective, simple, reasonable, clean, pure)
9
unreserved(adjective, clear, open, direct, free)
8
audible(adjective, visual, clear, sound, sharp)
8
chaste(adjective, simple, soft, pure, shy)
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APASmart Define. (2016). plain thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/plain/thesaurus/synonyms
ChicagoSmart Define. 2016. "plain thesaurus" https://smartdefine.org/plain/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, plain thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/plain/thesaurus/synonyms>.
MLASmart Define. "plain thesaurus" 31 March 2016. Web. 21 September 2026. <https://smartdefine.org/plain/thesaurus/synonyms>