An Etymological Dictionary of Astronomy and Astrophysics

A classical variable which does not change upon spatial inversion, such as time, energy, angular momentum and so on. → odd parity.

Etymology (EN): Even, from O.E. efen “level; equal,” from P.Gmc. *ebnaz (cf. Ger. eben; Goth. ibns); → parity.

Etymology (PE): Hamâli, → parity; zowj “pair, couple; an even number,” from Ar.