An unfortunate pseudo-word that's entered the lexicon as the result of the political correctness movement, and the fact that most English-speakers are too lazy to want to write or read he or she every time a neutered pronoun needs to be used. When read aloud, this must be translated back to he or she (a noun phrase which is annoying enough by itself, as it is often homosyllabic with the noun it is supposed to denote; ie, he or she wears socks, as opposed to the person wears socks). Its sister forms include he/she and s/he.

Of course, we really ought to break down and just start using "it", but for some reason the pronoun "it" has come to connote something lower than humans on our great Hierarchy of All Things, so people get offended when you refer to them as an "it".