unit circle

noun

: a circle having a radius of 1

Examples of unit circle in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
To see how to create a 17-gon, start with a unit circle (where the radius equals one) and a point A on the circle. — Jack Murtagh, Scientific American, 12 Sep. 2024 The area of a unit circle is pi, as Newton well knew, so when x=1, the area under the curve is a quarter of the unit circle, . — Steven Strogatz, Quanta Magazine, 31 Aug. 2022 This is the region under the unit circle, defined by y=, that lies above the portion of the horizontal axis from 0 to x. — Steven Strogatz, Quanta Magazine, 31 Aug. 2022 Some may fall inside the unit circle, others right on it, and still others outside it. — Quanta Magazine, 14 May 2020 Since going a distance π takes you halfway around the unit circle, cos(π)=-1 and sin(π)=0, so eiπ=-1. — Lorenzo Sadun, Slate Magazine, 14 Mar. 2017

Word History

First Known Use

1852, in the meaning defined above

Time Traveler
The first known use of unit circle was in 1852

Rhymes for unit circle

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Browse Nearby Words

unit character
unit circle
unit class
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Cite this Entry

“Unit circle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unit%20circle. Accessed 31 Jul. 2026.

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