binary

American  

[bahy-nuh-ree, -ner-ee] / ˈbaɪ nə ri, -nɛr i /

adjective

1. consisting of, indicating, or involving two.

2. Mathematics.

   1. of or relating to a system of numerical notation to the base 2, in which each place of a number, expressed as 0 or 1, corresponds to a power of 2. The decimal number 58 appears as 111010 in binary notation, since 58 = 1 × 2 5 + 1 × 2 4 + 1 × 2 3 + 0 × 2 2 + 1 × 2 1 + 0 × 2 0 .

   2. of or relating to the digits or numbers used in binary notation.

   3. of or relating to a binary system.

   4. (of an operation) assigning a third quantity to two given quantities, as in the addition of two numbers.

3. Computers. of, relating to, or written in binary code; programmed or encoded using only the digits 0 and 1.

   All executable programs on the computer are stored in binary files.

4. Chemistry. noting a compound containing only two elements or groups, as sodium chloride, methyl bromide, or methyl hydroxide.

5. Metallurgy. (of an alloy) having two principal constituents.

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noun

• binaries
  plural

1. a whole composed of two.

2. Mathematics. a system of numerical notation to the base 2, in which each place of a number, expressed as 0 or 1, corresponds to a power of 2.

   to convert decimal to binary.

3. Also called binary number.  Mathematics. a number expressed in the binary system of notation.

4. Computers. binary code.

5. Computers. an executable file stored in binary format.

6. Astronomy. binary star.

binary British  

/ ˈbaɪnərɪ /

adjective

1. composed of, relating to, or involving two; dual

2. maths computing of, relating to, or expressed in binary notation or binary code

3. (of a compound or molecule) containing atoms of two different elements

4. metallurgy (of an alloy) consisting of two components or phases

5. (of an educational system) consisting of two parallel forms of education such as the grammar school and the secondary modern in Britain

6. maths logic (of a relation, expression, or operation) applying to two elements of its domain; having two argument places; dyadic

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noun

1. something composed of two parts or things

2. astronomy See binary star

3. short for binary weapon

binary Scientific  

/ bī′nə-rē /

1. Having two parts.

2. Mathematics Based on the number 2 or the binary number system.

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binary Cultural  

1. Anything composed of two parts. In modern computers, information is stored in banks of components that act like switches. Since switches can be either on or off, they have a binary character, and we say that the computer uses “binary arithmetic” to do its work.

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Other Word Forms

Noun Inflected Forms

• binaries
  plural

Etymology

Origin of binary

First recorded in 1350–1400; Middle English, from Late Latin bīnārius, equivalent to bīn(ī) ( see bin-) + -ārius -ary

Explanation

Something that can be broken into two categories is binary. Binary means something close to dual or double. You can remember what binary means if you know that bi- means two. Black and white are often set up as a binary, as are light and dark and good and evil. One binary we see all the time is the male and female symbols you see on bathroom doors. In computing, binary is a code of zeros and ones (computer programming) also known as base two. A binary is also a double star — two stars revolving around each other.

Example Sentences

See Examples For:

binary binaries

Stars in a very close binary can become tidally locked, meaning each star rotates on its axis at the same rate that the pair orbits one another.

From Science Daily ● Aug. 23, 2026

Scientists believe that S301 was once part of a binary star system that was torn apart by the almighty pull of the black hole.

From Barron's ● Aug. 20, 2026

They involve binary contracts that resolve based on whether certain events happen or not, using some complex math to factor in a probability of an outcome.

From Salon ● Aug. 12, 2026

More often than not, teams view the decision as binary.

From The Wall Street Journal ● Aug. 10, 2026

Such a binary is called a nova and has quite a different origin from a supernova.

From "Cosmos" by Carl Sagan

"If the orbital speed of the binaries is less than the kick speed, the wide binaries will become gravitationally unbound," Fuller explains.

From Science Daily ● Jul. 21, 2026

One of the stellar binaries, known as G203-47, is now officially the ninth closest white dwarf to the Sun.

From BBC ● Jul. 14, 2026

The trilogy artfully transcends the binaries of empire, overlaying the brute facts of economy and race with ripping anecdotes, splendid uniforms and sensual Indian architecture.

From The Wall Street Journal ● Apr. 23, 2026

The museum has physically invalidated the binaries of center and periphery, major and minor arts.

From Los Angeles Times ● Apr. 22, 2026

The pale binaries sat stolidly on the horizon, forty degrees apart.

From Faithfully Yours by Lou Tabakow