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1. Having or exercising the ability to reason. See Synonyms at logical.
2. Consistent with or based on reason or good judgment; logical or sensible: rational decisions.
3. Of sound mind; sane: wondered if the eccentric neighbor was not completely rational.
4. Mathematics Capable of being expressed as a quotient of integers.
A rational number.
[Middle English racional, from Old French racionel, from Latin ratiōnālis, from ratiō, ratiōn-, reason; see 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.
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|Noun||1.||rationalness - the quality of being consistent with or based on logic|
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
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.