Not valid; not true, correct, acceptable or appropriate.
Suffering from disability or illness.
Intended for use by an invalid.
To make invalid or affect with disease.
To exempt from (often military) duty because of injury or ill health.
Logically sound; not self-contradictory or otherwise absurd.
Healthy or balanced intellectually; exhibiting reasonableness.
Of an algebraic expression, capable of being expressed as the ratio of two polynomials.
Expressing the type, structure, relations, and reactions of a compound; graphic; said of formulae.
Of a number, capable of being expressed as the ratio of two integers.
Expressing a physical object.
Capable of reasoning.
A rational number: a number that can be expressed as the quotient of two integers.
The breastplate worn by Israelite high priests.