Ratio n. : The relation which one quantity or magnitude has to another of the same kind. It is expressed by the quotient of the division of the first by the second; thus, the ratio of 3 to 6 is expressed by / or /; of a to b by a/b; or (less commonly) the second term is made the dividend; as, a:b = b/a.

Ratio n. : Hence, fixed relation of number, quantity, or degree; rate; proportion; as, the ratio of representation in Congress.

Example:
Ratio........................................?

Taxonomy
ratio, quantities, oranges, dilution, dilution factor, word ratio, weight ratio, free encyclopedia, Ratio decidendi, Proportions, fraction, physical quantities, relative quantities, variable quantities, cement, 3 apples, Direct proportion, speed.

Defination from the web:
ratio might be physical quantities such as speed or temperature, or may simply refer to amounts of particular objects. ... If the ratio deals with objects or amounts of objects, this is often expressed as "for every two parts of the first quantity ...