Definition:Operation/Arity

Definition
The arity of an operator is the number of operands it uses.

The arity of an operator may be, in general, any number.

It may even be infinite.

Ternary
And so on.

Linguistic Note
The term arity is a neologism generated from the -ary suffix of the specific terms unary, binary and so on.

Also known as
An older term for arity that can sometimes be seen is valency, which may be considered more acceptable to those who prefer linguistic purity.