trig·​o·​nom·​e·​try | \ˌtri-gə-ˈnä-mə-trē \

Definition of trigonometry 

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

Examples of trigonometry in a Sentence

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Critical mathematical applications such as Fourier transforms, Riemann zeta functions, Gaussian distributions, roots of unity, integrating over polar coordinates and pretty much anything involving trigonometry employs pi. Randyn Charles Bartholomew, Scientific American, "Let's Use Tau--It's Easier Than Pi," 25 June 2014 Fans watched in physical discomfort as Bryson DeChambeau consulted his trusty yardage/topography/trigonometry map on every shot, chip and putt. Daniel Rapaport,, "FORE Questions: On Slow Play, 'Backstopping" and Offbeat U.S. Open Storylines," 11 June 2018 Game designer: Mathematics is involved in game theory, and programmers regularly utilize trigonometry, physics and calculus., "Jobs add up for students proficient in math," 19 Apr. 2018 Here’s the best-case scenario: a bad guy comes in with an AR-15, Mr. Hanabrink pauses his trigonometry lesson, pulls a .22 from under his sweater vest, calmly enters the fray, and delivers the kill shot. Dave Holmes, Esquire, "'Arm the Teachers' Is the Vain and Foolish Fantasy of a Vain and Foolish President," 23 Feb. 2018 In addition to trigonometry homework and essays on Shakespeare, American students are being tasked with an impossible request: ensure your own safety if a shooter arrives on campus. Ella Cerón, Teen Vogue, "Students Demonstrate How to Survive a School Shooting," 23 Mar. 2018 Periodic functions are repeating patterns like the undulations of a sine wave in trigonometry. Kenneth Chang, New York Times, "Robert P. Langlands Is Awarded the Abel Prize, a Top Math Honor," 20 Mar. 2018 But pi also has countless applications beyond geometry and trigonometry. Aristos Georgiou, Newsweek, "Pi Day: What Is Pi and Why Is It so Important?," 14 Mar. 2018 His sine law allows anyone with a decent grounding in trigonometry to use a pendulum to determine their latitude. Alicia Ault, Smithsonian, "How Does Foucault’s Pendulum Prove the Earth Rotates?," 3 Feb. 2018

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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Last Updated

11 Oct 2018

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Time Traveler for trigonometry

The first known use of trigonometry was in 1614

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English Language Learners Definition of trigonometry

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

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