n. (pl. -ies) 1 a correct proportion of the parts of a thing; balance, harmony. b beauty resulting from this. 2 a a structure that allows an object to be divided into parts of an equal shape and size and similar position to the point or line or plane of division. b the possession of such a structure. c approximation to such a structure. 3 the repetition of exactly similar parts facing each other or a centre. 4 Bot. the possession by a flower of sepals and petals and stamens and pistils in the same number or multiples of the same number. symmetric adj. symmetrical adj. symmetrically adv. symmetrize v.tr. (also -ise).
[ obs. F symmétrie or L summetria f. Gk (as SYN-, metron measure) ]