(archaic) The quality or state of being rational.

plural of rationalizing

(now rare) Rationally, reasonably.

rationing

(philosophy) The proposition that scientific theories, and any other claims to knowledge, can and should be rationally criticized, and, if they have empirical content, can and should be subjected to tests which may falsify them.

(chiefly Australia) Synonym of neoliberalism. / Used other than figuratively or idiomatically: see economic, rationalism.

(mathematics) A number that can be expressed as the ratio of two integers.

plural of rational number

(mathematics) The set of numbers that can be expressed as a ratio of integers, often denoted with the bold letter Q, or the blackboard bold letter ℚ.

(mathematics, complex analysis, algebraic geometry) Any function expressible as the quotient of two (coprime) polynomials (and which thus has poles at a finite, discrete set of points which are the roots of the denominator).