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top: surface view of cycloid scales of a bony fish
bottom: The parametric equations of this cycloid are
x = r(θ - sin θ),
y = r(1 - cos θ).cycloid
1. Resembling a circle.
a. Relating to or being a kind of fish scale that is thin, rounded, and smooth-edged and often shows concentric growth rings.
b. Having cycloid scales.
3. Psychology Afflicted with or relating to cyclothymia.
The curve traced by a point on the circumference of a circle that rolls on a straight line.
[French cycloïde, from Greek kukloeidēs, circular : kuklos, circle; see kwel- in Indo-European roots + -oeidēs, -oid.]
cy·cloi′dal (-kloid′l) adj.
1. (Mathematics) resembling a circle
2. (Zoology) (of fish scales) rounded, thin, and smooth-edged, as those of the salmon
3. (Psychiatry) psychiatry (of a type of personality) characterized by exaggerated swings of mood between elation and depression. See also cyclothymia
4. (Mathematics) geometry the curve described by a point on the circumference of a circle as the circle rolls along a straight line. Compare trochoid1
5. (Zoology) a fish that has cycloid scales
1. resembling a circle; circular.
a. (of the scale of a fish) smooth-edged and more or less circular in form.
b. (of a fish) having such scales.
3. Psychiatry. of or denoting a personality type characterized by wide fluctuations in mood within the normal range.n.
4. a curve generated by a point on the circumference of a circle that rolls, without slipping, on a straight line.
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|Noun||1.||cycloid - a line generated by a point on a circle rolling along a straight line|
curate cycloid - a cycloid generated by a point inside the rolling circle
prolate cycloid - a cycloid generated by a point outside the rolling circle
|Adj.||1.||cycloid - resembling a circle|
rounded - curving and somewhat round in shape rather than jagged; "low rounded hills"; "rounded shoulders"