bi·na·ry | \ˈbī-nə-rē, -ˌner-ē, -ˌne-rē \
plural binaries

Definition of binary 

(Entry 1 of 2)

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 … human sexuality is more complicated than the simple binary of "homosexuals" and "heterosexuals."Ms



Definition of binary (Entry 2 of 2)

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

3a 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)

4a 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 the binary opposition of male and female— Joan W. Scott

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Synonyms & Antonyms for binary

Synonyms: Adjective

bipartite, double, double-barreled, double-edged, dual, duplex, twin, twofold

Antonyms: Adjective


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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.

Examples of binary in a Sentence


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

Recent Examples on the Web: Noun

Pansexuality has much to do with the rejection of a gender binary to begin with. Stephen Daw, Billboard, "Everything You Need to Know About Pansexuality," 9 July 2018 Historically, drag kings have been thought of as cisgender women dressing up as cisgender men, but as fluid understandings of gender and sexuality evolve, the male/female binary of drag is fading. Kt Hawbaker,, "Chicago's drag kings are out to destroy 'toxic masculinity,' one sequin and pelvic thrust at a time," 4 Apr. 2018 Which means the guy not only knows about event horizons and gravitational lensing but stuff like tidal forces (what!), x-ray binaries (hey now!), and active galactic nuclei (oh my god!). Robbie Gonzalez, WIRED, "An Astronomer Explains Black Holes at 5 Levels of Difficulty," 5 July 2018 All of this means that Hera will benefit our understanding of binary asteroids along with advancing our planetary defense technology while operating in deep space. Avery Thompson, Popular Mechanics, "New Spacecraft Will Head to Binary Asteroid to Help Protect the Planet," 25 June 2018 Gender is so often an accidental inheritance — one that comes despite best efforts to disrupt the binary, to teach girls about astronauts and boys about baking. Heather Radke, Longreads, "A Beginner’s Guide to Fly Fishing With Your Father," 16 June 2018 Sula is one of a growing number of people who identify outside the gender binary and who use the pronouns they, them and theirs. Debra Malina,, "Getting over the angst in calling my transgender child 'they'," 10 July 2018 But thinking of sleep as a spectrum, rather than an awake/asleep binary, may go a long way toward directing future insomnia research. Katie Heaney, The Cut, "Why People With Insomnia Wake Up Feeling Like They Never Slept," 5 Apr. 2018 Today’s young people have bought into an idea of diversity that has evolved beyond a Black and white binary., "What Happened To All Of The Black Teen Shows?," 3 July 2018

Recent Examples on the Web: Adjective

The discovery of photography at the end of the 1830s was binary. Mark Feeney,, "At Yale: on the threshold and under the volcano," 6 July 2018 The Soviets wanted the equivalent of U.S. binary weapons — nerve agents made up of relatively harmless components that turned deadly when mixed. Fox News, "A Cold War poison resurfaces in a quiet English town," 23 Apr. 2018 By turning all types of information into the digits of binary code, computer networks encourage the consolidation of once-diverse media into data empires of unprecedented scope and power. Nicholas Carr,, "Is Facebook the problem with Facebook, or is it us?," 10 July 2018 Soviet leaders wanted the equivalent of U.S. binary weapons — agents made up of relatively harmless components that turn deadly when mixed, making them easier to operate than regular chemical weapons. Washington Post, "AP Explains: Novichok nerve agent that sickened UK couple," 5 July 2018 The Spanish capital has just wrapped up its 2018 week-long pride celebrations, whose main theme was a call for equality and greater visibility for people with non-binary gender identity. NBC News, "Transgender Miss Universe contender speaks up for trans kids," 13 July 2018 The binary 11011, for example, is just Going from left to right, the dots are worth 16, 8, 2, and 1 for a total of 27. Scientific American, "The Same, Only Different," 4 Apr. 2018 The role of coroner, which is the oldest elected office in the U.S., is increasingly important as trans and non-binary people fight to have their identities recognized in life and in death. Kristen Bellstrom, Fortune, "Maxine Waters, Donald Trump, #MeToo Stats: Broadsheet June 26," 26 June 2018 Magnetic materials are well suited to a binary information system. Martin Weil,, "Peter Gruenberg; won Nobel for work that led to quicker computers," 12 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'binary.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of binary


15th century, in the meaning defined at sense 1


1597, in the meaning defined at sense 1

History and Etymology for binary


see binary entry 2


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

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Last Updated

1 Oct 2018

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Time Traveler for binary

The first known use of binary was in the 15th century

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More Definitions for binary



English Language Learners Definition of binary

: relating to or consisting of two things or parts

: relating to or involving a method of calculating and of representing information especially in computers by using the numbers 0 and 1


bi·na·ry | \ˈbī-nə-rē \

Kids Definition of binary

: of, relating to, or being a number system with a base of 2 The two binary digits are 0 and 1.


bi·na·ry | \ˈbī-nə-rē, -ˌner-ē \

Medical Definition of binary 

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

2a : 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)

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More from Merriam-Webster on binary

Thesaurus: All synonyms and antonyms for binary

Spanish Central: Translation of binary

Nglish: Translation of binary for Spanish Speakers

Comments on binary

What made you want to look up binary? Please tell us where you read or heard it (including the quote, if possible).


one that holds something together

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