/trit/
[by analogy with bit]
n. One base-3 digit; the amount of information conveyed by a selection among one of three equally likely outcomes (see also bit). These arise, for example, in the context of a flag that should actually be able to assume three values -- such as yes, no, or unknown.
Trits are sometimes jokingly called 3-state bits. A trit may be semi-seriously referred to as a bit and a half, although it is linearly equivalent to 1.5849625 bits (that is, log2(3) bits).