Parity

The quality or condition of being equal or equivalent; A like state or degree; equality; close correspondence; analogy; as, parity of reasoning.

(obstetrics) the number of liveborn children a woman has delivered; "the parity of the mother must be considered"; "a bipara is a woman who has given birth to two children"

(physics) parity is conserved in a universe in which the laws of physics are the same in a right-handed system of coordinates as in a left-handed system

(mathematics) a relation between a pair of integers: if both integers are odd or both are even they have the same parity; if one is odd and the other is even they have different parity; "parity is often used to check the integrity of transmitted data"

(computer science) a bit that is used in an error detection procedure in which a 0 or 1 is added to each group of bits so that it will have either an odd number of 1's or an even number of 1's; e.g., if the parity is odd then any group of bits that arrives with an even number of 1's must contain an error

functional equality