text: wht is a sex?   sex has a number of common meanings: sexual activities.  sexual intercourse - or vaginal intercourse; the physical act related to sexual reproduction.  a general topic of human or animal behavior. see human sexuality.  species gender - a biological distinction between two or more categories (sexes), such as male and female, which combine genetic material to reproduce. some linguists object to this use of the word gender, to avoid confusion with the word's meaning in grammar.  other things named sex or sex include:  sex is a 1926 play by mae west.  sex is a 1991 book by entertainer madonna and photographer steven meisel.  sex: the annabel chong story is a 1999 documentary film about porn star annabel chong.  sex was a boutique on kings road in the chelsea district of london. owned by malcolm mclaren, it was a seminal location in the emerging punk rock scene in the mid-1970s.  the "sex" assembly language mnemonic is often used for the "sign extend" machine instruction found in the pdp-11 and many other computer architectures.  sex is also a good mnemonic for advice about writing essays. it stands for sentence, explanation, and example.  sex is an abbreviation for the constellation sextans. http://en.wikipedia.org/wiki/sex_%28disa...  sex, in the scope of this article and category, refers to the male and female duality of biology and reproduction. the somewhat similar term gender has more to do with identity than biology. the concept is confined to organisms that reproduce sexually. http://en.wikipedia.org/wiki/sex...