34 entries under adjective topic. ×

8
incomprehensible
4
opaque
3
obscure
3
inexplicable
3
unpardonable
2
unintelligible
2
mysterious
2
unfathomable
1
ambiguous(clear, obscure, plain)
1
illegible
1
impenetrable
1
inarticulate
1
incoherent
1
indecipherable
1
indefensible
1
inexcusable
1
intricate(clear, simple, elaborate, complicated)
1
unclear
1
unreasonable
0
illogic
<12>
10 years ago|1.8k views|share |citing 
APASmart Define. (2016). understandable thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/understandable/thesaurus/antonyms
ChicagoSmart Define. 2016. "understandable thesaurus" https://smartdefine.org/understandable/thesaurus/antonyms (accessed September 23, 2026).
HarvardSmart Define 2016, understandable thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/understandable/thesaurus/antonyms>.
MLASmart Define. "understandable thesaurus" 31 March 2016. Web. 23 September 2026. <https://smartdefine.org/understandable/thesaurus/antonyms>