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Webster 1913 Edition

(ĭr-răsh′ŭn-al)

Adj.

[L.

irrationalis

: cf. F.

irrationnel

. See

not, and

Not rational; void of reason or understanding;

as, brutes are

irrational

animals

It seemed utterly

irrational

any longer to maintain it.

I. Taylor.

Syn. – Absurd; foolish; preposterous; unreasonable; senseless. See

Adj.

[L. irrationalis; in and rationalis, from ratio.]

Not rational; void of reason or understanding. Brutes are irrational animals.

Not according to the dictates of reason; contrary to reason; absurd. To pursue a course of life which destroys happiness, is irrational.