90 entries under straightforward topic. ×

1
outspoken(open, honest, true, straight)
1
phlegmatic(adjective, tough, rational, sober)
1
plain(adjective, calm, open, tough, honest)
1
pragmatic(adjective, tough, rational, sober)
1
pretensionless(open, honest, true, straight)
1
prosaic(adjective, tough, rational, sober)
1
prosy(adjective, tough, rational, sober)
1
regular(open, honest, true, straight)
1
righteous(open, honest, true, straight)
1
saintly(open, honest, true, straight)
1
square(open, honest, true, straight)
1
stoic(adjective, tough, rational, sober)
1
sure enough(expression, honest, true, earnest)
1
true-blue(open, honest, true, straight)
1
trustworthy(adjective, open, honest, pure, true)
1
twenty-four carat(expression, honest, true, earnest)
1
unaffected(adjective, open, tough, honest, true)
1
undesigning(open, honest, true, straight)
1
undissembled(open, honest, true, straight)
1
unembellished(adjective, tough, rational, sober)
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APASmart Define. (2016). serious thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/serious/thesaurus/synonyms
ChicagoSmart Define. 2016. "serious thesaurus" https://smartdefine.org/serious/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, serious thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/serious/thesaurus/synonyms>.
MLASmart Define. "serious thesaurus" 24 February 2016. Web. 26 September 2026. <https://smartdefine.org/serious/thesaurus/synonyms>