SINCE 1828

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binomial

noun bi·no·mi·al \ bī-ˈnō-mē-əl \

Definition of binomial

1 :a mathematical expression consisting of two terms connected by a plus sign or minus sign

2 :a biological species name consisting of two terms

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binomial

adjective

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binomially

play \-mē-ə-lē\ adverb

See binomial defined for English-language learners

See binomial defined for kids

Examples of binomial in a Sentence

the binomial a + b

Recent Examples of binomial from the Web

Before binomials, names of plants in books were lists or strings of words that formed a kind of nuanced description.

— james prosek, New York Times, "A Botanist in Swedish Lapland," 16 May 2017

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

Origin and Etymology of binomial

New Latin binomium, from Medieval Latin, neuter of binomius having two names, alteration of Latin binominis, from bi- + nomin-, nomen name — more at name

NEW! Time Traveler

First Known Use: 1557

See Words from the same year

Other Mathematics and Statistics Terms

abscissa, denominator, divisor, equilateral, exponent, hypotenuse, logarithm, oblique, radii, rhomb

BINOMIAL Defined for English Language Learners

binomial

noun

Definition of binomial for English Language Learners

mathematics : an expression consisting of two terms connected by a plus sign or minus sign

Medical Dictionary

binomial

noun bi·no·mi·al \ bī-ˈnō-mē-əl \

medical Definition of binomial

:a biological species name consisting of two terms

—

binomial

adjective

Learn More about binomial

Britannica.com: Encyclopedia article about binomial

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serious difficulty or misfortune

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Examples: binomial in a Sentence