- (mathematics, programming, computer engineering) Of an operation, function, procedure, or logic gate, taking exactly one operand, argument, parameter, or input; having domain of dimension 1.
"Negation is a unary operation."
- Consisting of or involving a single element or component.
- (information theory) Unary coding, an entropy encoding for natural numbers.
- (mathematics) The unary numeral system; the bijective base-1 numeral system.