Definition of trigonometry in English:



mass noun
  • The branch of mathematics dealing with the relations of the sides and angles of triangles and with the relevant functions of any angles.

    • ‘Omar Khayyam, known chiefly in Europe as a poet, combined trigonometry and approximation theory to solve algebraic equations using geometry.’
    • ‘Indians also added to our knowledge of even more complicated branches of mathematics such as trigonometry and calculus.’
    • ‘Slowly Caroline turned more and more towards helping William with his astronomical activities while he continued to teach her algebra, geometry and trigonometry.’
    • ‘Because of the clarity and care with which his elementary texts on analytic geometry and trigonometry were written they are still in demand.’
    • ‘He studied a lot of mathematics in his own time including trigonometry, differential and integral calculus, and complex numbers long before he met these topics in his formal education.’
    • ‘In fact without the aid of the sine function and trigonometry it is hard to see how Hypsicles could have done better.’
    • ‘Most of his papers are solutions to problems posed by Euler on spherical geometry, trigonometry, series, differential geometry and differential equations.’
    • ‘With an interest in trigonometry, mathematical instruments, astronomy, and geography, Regiomontanus was in a good position to give a lead.’
    • ‘If you were a surveyor, you could measure angles and then use high-school trigonometry to calculate distances.’
    • ‘He would have an easier time teaching them trigonometry than the triangle.’
    • ‘There he gave courses on astronomy, celestial mechanics, the differential and integral calculus, the theory of probability, geometry and trigonometry.’
    • ‘This work is really the first in history on trigonometry as an independent branch of pure mathematics and the first in which all six cases for a right-angled spherical triangle are set forth.’
    • ‘Geometry, and its branch trigonometry, was the mathematics Indian astronomers used most frequently.’
    • ‘Lexell made major contributions to spherical geometry and trigonometry.’
    • ‘He graduated in 1860 with an outstanding report, which mentioned in particular his exceptional skills in mathematics, in particular trigonometry.’
    • ‘Omar Khayyam combined the use of trigonometry and approximation theory to provide methods of solving algebraic equations by geometrical means.’
    • ‘Moore wrote the sections on arithmetic, geometry, trigonometry and cosmography while the sections on algebra, Euclid and navigation were written by Perkins.’
    • ‘William's father wrote a number of successful textbooks on arithmetic, calculus and trigonometry, which brought in a comfortable income for the family.’
    • ‘My math class, trigonometry, will probably be the hardest one.’
    • ‘Cavalieri also wrote on conic sections, trigonometry, optics, astronomy, and astrology.’


Early 17th century: from modern Latin trigonometria (see trigon, -metry).