IRRATIONALLY
irrationally
(adverb) in an irrational manner; “they acted irrationally”
Source: WordNet® 3.1
Etymology
Adverb
irrationally (comparative more irrationally, superlative most irrationally)
In an irrational manner; without reason; in a manner contrary to reason
Synonym: absurdly
Antonyms
• rationally
Source: Wiktionary
Ir*ra"tion*al*ly, adv.
Definition: In an irrational manner. Boyle.
IRRATIONAL
Ir*ra"tion*al, a. Etym: [L. irrationalis: cf. F. irrationnel. See In-
not, and Rational.]
1. Not rational; void of reason or understanding; as, brutes are
irrational animals.
2. Not according to reason; absurd; foolish.
It seemed utterly irrational any longer to maintain it. I. Taylor.
3. (Math.)
Definition: Not capable of being exactly expressed by an integral number,
or by a vulgar fraction; surd; -- said especially of roots. See Surd.
Syn.
– Absurd; foolish; preposterous; unreasonable; senseless. See
Absurd.
Source: Webster’s Unabridged Dictionary 1913 Edition