Resembling a circle; having a circular form.
Specifically In ichthyology: More or less circular, with concentric striations: applied to the scales of certain fishes. See cut under scale.
Having somewhat circular scales, as a fish; specifically, pertaining to the Cycloidei.
noun.
A curve generated by a point in the circumference or on a radius of a circle when the circle is rolled along a straight line and kept always in the same plane.
noun.
In ichthyology, a cycloid fish; a fish with cycloid scales, or one of the Cycloidei.
In chem., containing a cycle or ring of atoms: used especially of the structure of organic compounds.