cycloid

American  

[sahy-kloid] / ˈsaɪ klɔɪd /

adjective

1. resembling a circle; circular.

2. (of the scale of a fish) smooth-edged, more or less circular in form, and having concentric striations.

3. (of a fish) having such scales.

4. Psychiatry. of or noting a personality type characterized by wide fluctuation in mood within the normal range.

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noun

1. a cycloid fish.

2. Geometry. a curve generated by a point on the circumference of a circle that rolls, without slipping, on a straight line.

cycloid British  

/ ˈsaɪklɔɪd /

adjective

1. resembling a circle

2. (of fish scales) rounded, thin, and smooth-edged, as those of the salmon

3. psychiatry (of a type of personality) characterized by exaggerated swings of mood between elation and depression See also cyclothymia

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noun

1. geometry the curve described by a point on the circumference of a circle as the circle rolls along a straight line Compare trochoid

2. a fish that has cycloid scales

cycloid Scientific  

/ sī′kloid′ /

1. Resembling a circle.

2. Thin, rounded, and smooth-edged, like a disk. Used of fish scales.

3. The curve traced by a point on the circumference of a circle that rolls on a straight line.

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Other Word Forms

• cycloidal adjective
• cycloidally adverb

Etymology

Origin of cycloid

First recorded in 1655–65, cycloid is from the Greek word kykloeidḗs like a circle. See cycl-, -oid

Example Sentences

Kahn played with natural light in the Fort Worth building, suffused with skylights, reflectors and cycloid barrel vaults.

From New York Times • May 4, 2022

These equations are a bit more complicated, but the derivation is somewhat similar to the equations for the cycloid.

From Textbooks • Mar. 30, 2016

In this project we look at two different variations of the cycloid, called the curtate and prolate cycloids.

From Textbooks • Mar. 30, 2016

A graph of a prolate cycloid is shown in the figure.

From Textbooks • Mar. 30, 2016

Now, although artists have not shown any admiration for the cycloid, as they have for the ellipse, yet the mathematicians have gazed upon it with great eagerness, and found it rich in intellectual treasures.

From The Atlantic Monthly, Volume 05, No. 30, April, 1860 by Various