Simple Definition of illogical

from our Learner's Dictionary

illogical

adjective

: not showing good judgment : not thinking about things in a reasonable or sensible way : not logical
It is illogical to think that things will change on their own.
an illogical argument
You're being completely illogical.

Cite this Entry

“Illogical.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/illogical. Accessed 10 Jul. 2026.

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