Sex, n. [L. sexus: cf. F. sexe.] 1. The distinguishing peculiarity of male or female in both animals and plants; the physical difference between male and female; the assemblage of properties or qualities by which male is distinguished from female. 2. One of the two divisions of organic beings formed on the distinction of male and female. 3. Bot. (a) The capability in plants of fertilizing or of being fertilized; as, staminate and pistillate flowers are of opposite sexes. (b) One of the groups founded on this distinction. The sex, the female sex; women, in general. © Webster 1913.