50 entries under illogical topic. ×

23
baseless(adjective, reason, poor, foolish, true)
20
unfounded(adjective, reason, foolish, true, crazy)
15
unsound(adjective, foolish, unreasonable, error, reasoning)
12
idle(adjective, reason, false, true, worthless)
12
unjustified(adjective, reason, unwarranted, untrue, justification)
10
unreasonable(adjective, poor, foolish, reasoning, irrational)
6
fallacious(adjective, poor, foolish, unreasonable, error)
5
bottomless(adjective, reason, false, true, senseless)
4
absurd(adjective, foolish, unreasonable, irrational)
4
invalid(foolish, unreasonable, reasoning, irrational)
4
irrational(adjective, foolish, unreasonable, defended)
4
ridiculous(adjective, foolish, unreasonable, defended)
4
sophistic(adjective, foolish, unreasonable, irrational)
4
specious(adjective, foolish, unreasonable, irrational)
4
vain(adjective, false, empty, worthless, untrue)
2
crazy(foolish, unreasonable)
2
foolish(adjective, unreasonable)
2
foundationless(adjective, reason, false, unwarranted, untrue)
1
mad(foolish, unreasonable, irrational, unreasoned)
1
nutty(foolish, unreasonable, irrational, unreasoned)
<123>
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APASmart Define. (2015). groundless thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/groundless/thesaurus/synonyms
ChicagoSmart Define. 2015. "groundless thesaurus" https://smartdefine.org/groundless/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, groundless thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/groundless/thesaurus/synonyms>.
MLASmart Define. "groundless thesaurus" 14 April 2015. Web. 23 September 2026. <https://smartdefine.org/groundless/thesaurus/synonyms>