parity
1. par.i.ty \'par-*t-e-\ n [L paritas, fr. par equal] 1: the quality or state of being equal or equivalent 2a: equivalence of a commodity price expressed in one currency to its price expressed in another 2b: equality of purchasing power established by law between different kinds of money at a given ratio 3: an equivalence between farmers' current purchasing power and their purch asing power at a selected base period maintained by government support of agricultural commodity prices 2. parity n : the state or fact of having borne offspring; also : the number o f children previously borne
Webster's English Dictionary