trochoid

[ troh-koid ]

noun

1. Geometry. a curve traced by a point on a radius or an extension of the radius of a circle that rolls, without slipping, on a curve, another circle, or a straight line. Equation: x = aθ − b sin θ, y = a − b cos θ.

adjective

1. rotating on an axis, as a wheel.

trochoid

/ ˈtrəʊkɔɪd /

noun

1. the curve described by a fixed point on the radius or extended radius of a circle as the circle rolls along a straight line

adjective

1. rotating or capable of rotating about a central axis
2. anatomy (of a structure or part) resembling or functioning as a pivot or pulley

Derived Forms

• troˈchoidally, adverb

Other Words From

• tro·choidal adjective
• tro·choidal·ly adverb

Word History and Origins

Origin of trochoid¹

First recorded in 1695–1705, trochoid is from the Greek word trochoeidḗs round like a wheel. See troche, -oid

Word History and Origins

Origin of trochoid¹

C18: from Greek trokhoeidēs circular, from trokhos wheel

Example Sentences

Then any point in the circumference of the half-crown will move through a curve called a ‘trochoid.’

From Project Gutenberg