trig·​o·​nom·​e·​try | \ ˌtri-gə-ˈnä-mə-trē How to pronounce trigonometry (audio) \

Definition of trigonometry

: the study of the properties of triangles and trigonometric functions and of their applications

Examples of trigonometry in a Sentence

Recent Examples on the Web Algebra II is frequently combined with trigonometry in the third year of high school math. Washington Post, "Virginia allies with, then backs away from, controversial math anti-tracking movement," 6 Apr. 2021 Mary Fairfax Somerville, who was deliberately kept out of the schoolroom by her practical parents, discovered Euclid in her family’s library and moved on from geometry to trigonometry and astronomy. Washington Post, "Meet the forgotten rebels and quiet revolutionaries of women’s history," 5 Mar. 2021 The teams from China and Nepal used everything from old-fashioned trigonometry and surveying equipment like the theodolite, to satellite positioning and gravity meters. Eric Bellman, WSJ, "Mount Everest Just Got Taller," 8 Dec. 2020 The school has no math classes beyond algebra and geometry, so the hero’s father persuades him to learn trigonometry and calculus on his own to pursue his dream of going to space. Washington Post, "Progressive education hard to pin down because it’s everywhere," 4 Nov. 2020 Without formal education Washington learned mathematics, trigonometry, and land surveying., "My favorite American patriot," 20 Aug. 2020 The first is to measure Everest the old-fashioned way using trigonometry. Joanna Slater, The Denver Post, "Is Mt. Everest shrinking? Nepal on a mission to measure the world’s tallest mountain.," 21 Oct. 2019 The first is to measure Everest the old-fashioned way using trigonometry. Joanna Slater, Washington Post, "Is Mount Everest shrinking? Nepal is on a mission to find out.," 21 Oct. 2019 Today, Renee is an A+ student and is doing trigonometry and precalculus. Kristen Taketa, San Diego Union-Tribune, "Here are San Diego County’s five Teachers of the Year," 7 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'trigonometry.' 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 trigonometry

1614, in the meaning defined above

History and Etymology for trigonometry

New Latin trigonometria, from Greek trigōnon + -metria -metry

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Time Traveler for trigonometry

Time Traveler

The first known use of trigonometry was in 1614

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Statistics for trigonometry

Last Updated

8 May 2021

Cite this Entry

“Trigonometry.” Dictionary, Merriam-Webster, Accessed 9 May. 2021.

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More Definitions for trigonometry



English Language Learners Definition of trigonometry

: a branch of mathematics that deals with relationships between the sides and angles of triangles

More from Merriam-Webster on trigonometry

Nglish: Translation of trigonometry for Spanish Speakers Encyclopedia article about trigonometry

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