rational definition - Dictionary

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rational

ra·tion·al [ rásh'n'l ]

adjective

Definition:

1. reasonable and sensible: governed by, or showing evidence of, clear and sensible thinking and judgment, based on reason rather than emotion or prejudice

2. able to think clearly and sensibly: able to think clearly and sensibly, unimpaired by physical or mental condition, strong emotion, or prejudice

I can't be rational when so many people give me conflicting advice.

3. in accordance with reason and logic: presented or understandable in terms that accord with reason and logic or with scientific knowledge

a rational explanation

4. able to reason: endowed with the ability to reason, as opposed to being governed solely by instinct and appetite

5. mathematics expressible as ratio of polynomials: in mathematics, able to be expressed exactly as the quotient of two whole numbers or polynomials

a rational function

noun

Definition:

mathematics
Same as rational number

[14th century. < Latin rationalis< ratio (see ratio)]

ra·tion·al·ly adverb

ra·tion·al·ness noun

Word Usage


	Do not confuse rational and rationale, which are linked by the idea of "reason" but otherwise differ in meaning, spelling, and pronunciation. Rational is an adjective meaning "reasonable and sensible" (a perfectly rational argument), whereas rationale is a noun meaning "the reasoning that underlies something" (explained the rationale behind the new guidelines).