trigonometry

noun

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

: 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

Calculator App: Apple is giving its Calculator app an upgrade by adding new features like the ability to enter and continue to view complete expressions (with trigonometry, parentheses, and multiple operations) before pressing equals to see the final answer. —Brenda Stolyar, WIRED, 21 Jan. 2025

Although the Pythagorean theorem has been proved with algebra and geometry, mathematicians previously thought that it couldn’t be proved using trigonometry. —Alexa Robles-Gil, Smithsonian Magazine, 30 Oct. 2024

Related article Turbulent skies of Vincent Van Gogh’s ‘The Starry Night’ align with a scientific theory, study finds Jackson and Johnson’s study outlines five new ways of proving the theorem using trigonometry, and their method reveals five more proofs for 10 total. —Katie Hunt, CNN, 29 Oct. 2024

Ex-student Charles is a trigonometry wiz, but all the logic in the world can’t prevent his longing for death. —Armond White, National Review, 25 Sep. 2024

Word History

Etymology

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

First Known Use

1614, in the meaning defined above

Phrases Containing trigonometry

• spherical trigonometry

Kids Definition

trigonometry

noun

trig·​o·​nom·​e·​try ˌtrig-ə-ˈnäm-ə-trē 

: a branch of mathematics concerned with the study of the properties of triangles and trigonometric functions and of their practical uses

Etymology

from scientific Latin trigonometria, literally "triangle measurement," derived from Greek tri- "three" and Greek gonia "angle" and Greek -metria "art or science of measuring"