(computing) The number obtained by changing the numeric sign of a number. This may or may not be the twos complement, depending on the way numbers are stored.

(computing) The number, obtained by complementing every bit of a given number, which produces all ones when exclusive ored with the given number.

The number which, added to the given n-digit number in radix r, results in rⁿ. In binary (r=2), this is the two's complement.

plural of complement system

(biology) The air that can be drawn into the lungs in addition to the tidal air, by the deepest possible inhalation.

(set theory) The set that contains exactly those elements belonging to the universal set but not to a given set.

(set theory, of set A "in" set B) The set containing exactly those elements belonging to B but not to A.

(mathematics) The residual operation of a Heyting algebra when considered as a residuated lattice whose monoid operation is the meet operation. Equivalently, the relative pseudo-complement of a with respect to b is the supremum of the set of all z such that z∧a⩽b, where ∧ denotes the meet operation of the given Heyting algebra.

The number which, added to the given n-digit number in radix r, results in rⁿ-1. In binary (r=2), this is the ones' complement; in decimal (r=10), this is the nines' complement.

plural of absolute complement