imaginary unit


Definition of imaginary unit

: the positive square root of minus 1 denoted by i or + √-1

Examples of imaginary unit in a Sentence

Recent Examples on the Web

The introduction of this one new non-real number — i, the imaginary unit — launched an entirely new mathematical world to explore. Quanta Magazine, "The (Imaginary) Numbers at the Edge of Reality," 25 Oct. 2018

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

First Known Use of imaginary unit

circa 1911, in the meaning defined above

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Statistics for imaginary unit

Last Updated

14 Oct 2019

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The first known use of imaginary unit was circa 1911

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