Rational

Pronunciation

• enPR: ră'sh(É™)nÉ™l, IPA: /ˈræʃ(É™)nÉ™l/

Alternative forms

• rationall obsolete

From Old French rationel, rational, from Latin rationalis ("of or belonging to reason, rational, reasonable"), from ratio ("reason")

Full definition of rational

Adjective

1. Capable of reasoning.
• 2001, Mark Sainsbury, Logical Forms — An Introduction to Philosophical Logic Chapter 1, The utility of valid arguments is a monument to our frailty: to the fact that we are not completely rational beings.
2. Man is a rational creature.
3. Logically sound; not contradictory or otherwise absurd.''His statements were quite rational.
4. (of a person or personal characteristics) Healthy or balanced intellectually; exhibiting reasonableness.rational conduct
5. (mathematics, arithmetic, number theory, not comparable) Of a number, capable of being expressed as the ratio of two integers.''$\backslash tfrac\{3\}\{4\}$ is a rational number, but √

1. (mathematics, arithmetic, not comparable) Of an algebraic expression, capable of being expressed as the ratio of two polynomials.
2. (chemistry) Expressing the type, structure, relations, and reactions of a compound; graphic; said of formulae.

Antonyms

• (reasonable) absurd, irrational, nonsensical
• (capable of reasoning) arational, irrational, non-rational
• (number theory) irrational

Related terms

From Old French rational, from Medieval Latin rationale ("a pontifical stole, a pallium, an ornament worn over the chasuble"), neuter of Latin rationalis ("rational"), for which see the first etymology.

Noun

1. (mathematics) A rational number: a number that can be expressed as the quotient of two integers.The quotient of two rationals is again a rational.
2. A rational being.

Anagrams

• notarial