illogical
UK: ɪˈlɒdʒɪk(ə)l | US: ɪˈlɑːdʒɪk(ə)l
adj. lacking sense or sound reasoning; contrary to logic
adj. not following the principles of logic
The word "illogical" combines the negative prefix "il-" (a variant of "in-" used before "l"), derived from Latin "in-" meaning "not," with "logic," from Greek "logikē" (reasoning). The suffix "-al" (from Latin "-alis") forms adjectives. Thus, "illogical" literally means "not pertaining to reason." The term emerged in the early 17th century to describe ideas or arguments that defy rational principles.
His argument was so illogical that no one could take it seriously.
It’s illogical to expect different results without changing your approach.
The plot of the movie was entertaining but utterly illogical.
She dismissed the claim as illogical and unsupported by evidence.
Fear often leads people to make illogical decisions.