I'm sure it is ternary, because the ?: operator uses 3 statements, and tern means 3. I've never heard of a trinary operator but it does sound like it follows unary > binary > trinary?

A quick google shows that people do refer to it as trinary in languages such as java and phython, but in C,C++,C# it is ternary. Go figure? lol.

Trinary is a number base, that uses the characters 0,1 and 2. Just like binary uses 0 and 1.