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1. Irrational thought, expression, or behavior; irrationality.
2. Belief in feeling, instinct, or other nonrational forces rather than reason.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ɪˈræʃ ə nlˌɪz əm)

1. irrationality in thought or action.
2. a theory that nonrational forces govern the universe.
ir•ra′tion•al•ist, adj., n.
ir•ra`tion•al•is′tic, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


1. a theory that nonrational forces govern the universe.
2. any attitude or set of beliefs having a nonrational basis, as nihilism. — irrationalist, n., adj.irrationalistic, adj.
See also: Philosophy
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
One myth of dialectics of ecological crisis is associated with animal irrationalism, with apologetics of political violence.
India's first prime minister, Jawaharlal Nehru, argued that unlike religion - which tends to produce "intolerance, credulity and superstition, emotionalism and irrationalism" and "a temper of a dependent, unfree person" - a scientific temper "is the temper of a free man."
For Mann, the ambitions of Keynesianism (whether narrowly economic or broadly political) are to 'save civilization' (from 'mindless irrationalism' and 'arbitrary inequalities')--though the new knowledge that would ground an associated 'elite-civilizing project' would be 'illiberal', posing political solutions to problems revolution proved unable to dissolve (pp.66-70).
Was it the result of his usual irrationalism, or of domestic politics?
The Freethinker attacked religion, irrationalism, and all kinds of censorship, and did so with wit and fervor.
SHE WRITES THAT OUR "TIME OF MORAL panic" is unprecedented, "driven by secularist rather than religious irrationalism." We are in the grip of a fever induced by an overdose of gender theory and the elevation of sexual satisfaction to a moral right and duty.
I had no control over it and the pain was building but it was not physical pain, rather a sense of irrationalism with uncontrollable anxiety.
It is the apex of irrationalism. It promotes and glorifies irrationalism.
Having established Islamophobia as an undeniable fact, the Republican presidential candidate has now managed to expose the profound irrationalism of such tribalist hatreds.
If violence and irrationalism is a strength, I don't have it, I still regret killing that rat.
Facets of Russian Irrationalism Between Art and Life: Mystery Inside Enigma
The carnage at the BKU and earlier at the Army School in Peshawar is a reminder that irrationalism is seeping in and needs to be repulsed.