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, 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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Time Traveler for imaginary unit

Time Traveler

The first known use of imaginary unit was circa 1911

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Dictionary Entries Near imaginary unit

imaginary part

imaginary unit


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Statistics for imaginary unit

Cite this Entry

“Imaginary unit.” Dictionary, Merriam-Webster, Accessed 25 Jan. 2022.

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