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Related to rationality: Bounded rationality


n. pl. ra·tion·al·i·ties
1. The quality or condition of being rational.
2. A rational belief or practice.
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.


n, pl -ties
1. the state or quality of being rational or logical
2. the possession or utilization of reason or logic
3. a reasonable or logical opinion
4. (Economics) economics the assumption that an individual will compare all possible combinations of goods and their prices when making purchases
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌræʃ əˈnæl ɪ ti)

n., pl. -ties.
1. the state or quality of being rational.
2. the possession or exercise of reason.
3. agreeableness to reason.
4. a reasonable view, practice, etc.
[1560–70; < Late Latin ratiōnālitās reasonableness. See rational, -ity]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rationality - the state of having good sense and sound judgment; "his rationality may have been impaired"; "he had to rely less on reason than on rousing their emotions"
saneness, sanity - normal or sound powers of mind
2.rationality - the quality of being consistent with or based on logic
logicality, logicalness - correct and valid reasoning
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


1. What is sound or reasonable:
Idiom: rhyme or reason.
2. Exact, valid, and rational reasoning:
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


[ˌræʃəˈnælɪtɪ] Nracionalidad f
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


n (of person, action, thinking)Vernünftigkeit f, → Rationalität f; (of activity, solution)Vernünftigkeit f; (Med) → klarer Verstand
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


(ˈraʃənl) adjective
1. able to think, reason and judge etc. Man is a rational animal.
2. sensible; reasonable; logical; not (over-) influenced by emotions etc. There must be a rational explanation for those strange noises
ˈrationally adverb
ˌrationˈality noun
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.
References in classic literature ?
"Rationality gelded to sentiment," the White Logic grins.
I could do with less caressing and more rationality. I should like to be less of a pet and more of a friend, if I might choose; but I won't complain of that: I am only afraid his affection loses in depth where it gains in ardour.
Not only the rationality of millenniums--also their madness, breaketh out in us.
It did not accord with the rationality of plan, the moderation in expense, or even the unselfish warmth of heart, which she had believed herself to discern in him yesterday.
He has the religion of the matter, in believing what is to happen will happen; and with such a consolation, it won't be long afore he submits to the rationality of killing a four-footed beast to save the lives of human men.
To be a second time disappointed in the same way was an instance of very severe ill-luck; and his indignation was such, that had it not been for delicacy towards his friend, and his friend's youngest sister, he believed he should certainly attack the baronet on the absurdity of his proceedings, and argue him into a little more rationality. He believed this very stoutly while he was in Mansfield Wood, and all the way home; but there was a something in Sir Thomas, when they sat round the same table, which made Mr.
Charles Musgrove was civil and agreeable; in sense and temper he was undoubtedly superior to his wife, but not of powers, or conversation, or grace, to make the past, as they were connected together, at all a dangerous contemplation; though, at the same time, Anne could believe, with Lady Russell, that a more equal match might have greatly improved him; and that a woman of real understanding might have given more consequence to his character, and more usefulness, rationality, and elegance to his habits and pursuits.
Finally, I shook the thing, hoping to recall it for a moment to rationality.
While it had always been difficult for me to look upon these things as other than slimy, winged crocodiles--which, by the way, they do not at all resemble--I was now forced to a realization of the fact that I was in the hands of enlightened creatures--for justice and grati-tude are certain hallmarks of rationality and culture.
Why, mademoiselle, is it possible that anybody with a grain of rationality should feel enthusiasm about a mere name, and that name England?
The widest empirical laws of sequence known at any time can only be "explained" in the sense of being subsumed by later discoveries under wider laws; but these wider laws, until they in turn are subsumed, will remain brute facts, resting solely upon observation, not upon some supposed inherent rationality.
"Why, her mother won't let them get engaged." And he leaned back in his chair in radiant rationality.