20 entries under reasoning topic. ×

17
invalid(adjective, false, useless, unfit)
17
unsound(adjective, false, defended, indefensible)
12
illogical(adjective, sense, defended, indefensible)
9
fallacious(adjective, false)
9
unreasonable(adjective, defended, verbal attack)
8
groundless(adjective, defended, verbal attack)
5
unwarranted
3
false
2
inconclusive
2
inconsequent
2
inconsequential
2
incorrect
2
unscientific
1
inconsistent
1
unproved
0
fallible
0
absonant
0
absonous
0
non sequitur(expression, idiom)
0
not following(expression, idiom)
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APASmart Define. (2016). untenable thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/untenable/thesaurus/synonyms
ChicagoSmart Define. 2016. "untenable thesaurus" https://smartdefine.org/untenable/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, untenable thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/untenable/thesaurus/synonyms>.
MLASmart Define. "untenable thesaurus" 29 March 2016. Web. 26 September 2026. <https://smartdefine.org/untenable/thesaurus/synonyms>