pertaining to a function whose domain is a given set and whose range is contained in that set.
Origin of unary
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
consisting of, or affecting, a single element or component; monadic
Word Origin for unary
C16 (in the obsolete sense: a unit): from Latin unus one + -ary
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