11
easy(adjective, quiet, clear, open, light)
11
express(verb, adjective, clear, simple, right)
11
guileless(adjective, open, direct, free, simple)
11
homey(adjective, quality, open, simple, easy)
11
indisputable(adjective, clear, simple, true, straightforward)
11
legible(adjective, clear, simple, easy, sharp)
11
observable(adjective, clear, see, substantial, obvious)
11
out-and-out(adjective, clear, complete, simple, flat)
11
outright(adjective, good, clear, open, direct)
11
perspicuous(adjective, clear, sharp, definite, distinct)
11
plane(noun, adjective, characteristic, calm, quiet)
11
routine(adjective, good, dull, clear, simple)
11
rustic(adjective, open, simple, easy, clean)
11
severe(adjective, calm, clear, simple, harsh)
11
smooth(adjective, characteristic, calm, clear, light)
11
unaffected(adjective, open, simple, tough, reasonable)
11
uncomplicated(adjective, clear, light, smooth, simple)
11
undiluted(adjective, strong, simple, clean, pure)
11
unmixed(adjective, strong, simple, clean, pure)
11
unqualified(adjective, clear, open, right, friendly)
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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>