binary

1 of 2

noun

bi·​na·​ry ˈbī-nə-rē  -ˌner-ē 

-ˌne-rē

plural binaries

1

: something made of two things or parts

specifically : binary star

2

mathematics : a number system based only on the numerals 0 and 1 : a binary (see binary entry 2 sense 3a) number system

42 is written as 101010 in binary.

3

: a division into two groups or classes that are considered diametrically opposite

Sam Killermann, a self-described "social justice comedian," is very serious about how far the complexities of identity go beyond the traditional binary of male or female.

—Katy Steinmetz

binary

2 of 2

adjective

1

: compounded or consisting of or marked by two things or parts

2

music

a

: duple

—used of measure or rhythm

b

: having two musical subjects or two complementary sections

a song in binary form

3

a

mathematics : relating to, being, or belonging to a system of numbers having 2 as its base

the binary digits 0 and 1

b

: involving a choice or condition of two alternatives (such as on-off or yes-no)

4

a

chemistry : composed of two elements (see element sense 2e), an element and a radical (see radical entry 2 sense 4) that acts as an element, or two such radicals

b

: utilizing two harmless ingredients that upon combining form a lethal substance (such as a gas)

binary weapons

5

: relating two logical or mathematical elements

a binary operation

6

: of or relating to the use of stable oppositions (such as good and evil) to analyze a subject or create a structural model

Many examples of recurrent binary contrasts can be found in Western religion, literature, and mythology: good versus bad, up versus down, male versus female, … young versus old, and so forth.

—Marvin Harris

Did you know?

The animals went in two by two, the elephant and the kangaroo. . .. It was a binary parade of sorts that went into Noah's ark "for to get out of the rain" - the critters were represented in pairs. If you recall those partnered beasts, you'll remember the etymology of binary, because it traces to the Latin bini, which translates as "two by two." Although "binary" can be used for anything with two parts, it is now used especially in relation to computers and information processing. Digital computers use the binary number system, which includes only the digits 0 and 1, to process even complex data. In binary form, for instance, the word HELLO looks like this: 1001000 1000101 1001100 1001100 1001111.

Synonyms of binary

Adjective

• dual
• twin

Examples of binary in a Sentence

Adjective

a binary star is a system of two stars that revolve around each other under their mutual gravitation

Recent Examples on the Web

Noun

Its approach is spatial and observational, less interested in the ideological binary of left and right than in the vast, complicated country that lies between. — Matthew Carey, Deadline, 23 Sep. 2026

The poems push against the binaries of leaving and being left and embrace ongoing love in the wake of loss. — Literary Hub, 17 Sep. 2026

Adjective

When the system is uncertain, the case can be escalated rather than forcing a binary conclusion. — Arpan Saxena, Forbes.com, 25 Sep. 2026

China has sought to capitalize on that opening, not necessarily by persuading countries to choose Beijing over Washington, but by making the choice less binary. — Luke Fountain, CNBC, 23 Sep. 2026

Word History

Etymology

Adjective and Noun

Late Latin binarius, from Latin bini two by two — more at bin-

First Known Use

Noun

15th century, in the meaning defined at sense 1

Adjective

1597, in the meaning defined at sense 1

Phrases Containing binary

• binary fission
• binary star
• binary system
• contact binary
• non-binary

Rhymes for binary

• finery
• winery
• refinery

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Kids Definition

binary

adjective

bi·​na·​ry

ˈbī-nə-rē

1

: compounded or consisting of or marked by two things or parts

2

: relating to, being, or belonging to a system of numbers having two as its base

the binary digits 0 and 1

3

: relating exactly two mathematical or logical elements at a time

multiplication is a binary operation

Medical Definition

binary

adjective

bi·​na·​ry ˈbī-nə-rē  -ˌner-ē 

1

: compounded or consisting of or marked by two things or parts

2

a

: composed of two chemical elements, an element and a radical that acts as an element, or two such radicals

b

: utilizing two harmless ingredients that upon combining form a lethal substance (as a gas)