Definitions
1.AdjectiveCapable of reasoning."Man is a rational creature."
2.AdjectiveLogically sound; not self-contradictory or otherwise absurd."His statements were quite rational."
3.AdjectiveHealthy or balanced intellectually; exhibiting reasonableness."rational conduct"
4.AdjectiveComprising, or expressible as, a ratio
Of a number, capable of being expressed as the ratio of two integers."¾ is a rational number, but √2 is an irrational number."
5.AdjectiveOf a number, capable of being expressed as the ratio of two integers."¾ is a rational number, but √2 is an irrational number."
6.AdjectiveOf an algebraic expression in indeterminates, or more generally a function: capable of being expressed as the ratio of two polynomials.
7.AdjectiveOf a variety: (informally) geometrically simple almost everywhere; (formally) birationally equivalent to projective space
8.AdjectiveOf a function between varieties: acting as a morphism on an open subset of its domain.
9.AdjectiveOf a point on an algebraic variety over a field: whose coordinates belong to the field in question (in contrast to those points of the variety which are only defined over the algebraic closure of the base field).
10.Adjectivesynonymous replacement for "condensed" in condensed formula.
11.NounA rational number: a number that can be expressed as the quotient of two integers."The quotient of two rationals is again a rational."
12.NounThe breastplate worn by Israelite high priests.