A trit is the trinary analog of the Bit: Where a bit says 2, a trit says 3. “Trit,” like “bit,” is overloaded:
An abstract trit (analog of the abstract bit) is an element of a set with three elements. Thus, there are three abstract trits. They are often denoted 0, 1, and 2.
A trit of data (analog of a bit of data) is the amount of data that can be carried by a physical object that can be placed in any one of three states.
A trit of information (analog of a Shannon) is the amount of information someone receives when they start out maximally uncertain about which one of three outcomes happened, and then they learn which one happened. A trit of information is bits of information.
A trit of evidence (analog of a bit of evidence) in favor of a hypothesis is an observation that is three times as likely if the hypothesis is true (versus if the hypothesis is false).
“Trit” is a portmanteau of “trinary digit.”