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Synonyms

trigonometry

American  
[trig-uh-nom-i-tree] / ˌtrɪg əˈnɒm ɪ tri /

noun

  1. the branch of mathematics that deals with the relations between the sides and angles of plane or spherical triangles, and the calculations based on them.


trigonometry British  
/ ˌtrɪɡəˈnɒmɪtrɪ, ˌtrɪɡənəˈmɛtrɪk /

noun

  1.  trig.  the branch of mathematics concerned with the properties of trigonometric functions and their application to the determination of the angles and sides of triangles. Used in surveying, navigation, etc

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

trigonometry Scientific  
/ trĭg′ə-nŏmĭ-trē /
  1. The study of the properties and uses of trigonometric functions.


Other Word Forms

  • nontrigonometric adjective
  • nontrigonometrical adjective
  • nontrigonometrically adverb
  • trigonometric adjective
  • trigonometrical adjective
  • trigonometrically adverb
  • untrigonometric adjective
  • untrigonometrical adjective
  • untrigonometrically adverb

Etymology

Origin of trigonometry

1605–15; < New Latin trigōnometria; trigon, -o-, -metry

Explanation

Trigonometry is the branch of math that focuses on triangles. A student who loves trigonometry may have a career as a mathematician in her future, or as a musician specializing in playing the triangle (just kidding). When you take a trigonometry class, you'll spend a lot of time learning about the sides and angles of triangles and the functions and relationships of their measurements. You'll memorize many formulas and encounter words like sine and cosine as well. The noun trigonometry has been around for hundreds of years, ever since a sixteenth century mathematician coined it, from the Greek trigonon, "triangle" and metron, "a measure."

Keep Reading on Vocabulary.com

Vocabulary lists containing trigonometry

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In the years following graduation, Jenner and Pratt would team up to produce “The Princes Of Malibu,” but only after Pratt, who was attending USC, almost flunked a course in business trigonometry.

From Los Angeles Times • Jan. 27, 2026

"For example, you have to memorise the exact values of trigonometry - and that's something we're not even asking A-level students to do," she said.

From BBC • Aug. 21, 2025

One dude jokes, “If only I remembered any trigonometry, this would be easy.”

From Slate • Jul. 7, 2025

You know what's more difficult than advanced trigonometry?

From Salon • Apr. 9, 2024

Norwood returned to Bermuda with his family, becoming a successful planter and devoting his leisure hours to his first love, trigonometry.

From "A Short History of Nearly Everything" by Bill Bryson