—adj.
1 a dual. b of or involving pairs.
2 of the arithmetical system using 2 as a base.
—n. (pl. -ies)
1 something having two parts.
2 a binary number.
3 a binary star.
Phrases and idioms:
binary code Computing a coding system using the binary digits 0 and
1 to represent a letter, digit, or other character in a computer (see BCD). binary compound Chem. a compound having two elements or radicals. binary fission the division of a cell or organism into two parts. binary number (or digit) one of two digits (usu. 0 or 1) in a binary system of notation. binary star a system of two stars orbiting each other.
binary system a system in which information can be expressed by combinations of the digits 0 and
1 (corresponding to 'off' and 'on' in computing). binary tree a data structure in which a record is branched to the left when greater and to the right when less than the previous record.
Etymology: LL binarius f. bini two together
Useful english dictionary. 2012.