What is of or pertaining to the Cycloidei. Cycloid scale (Zoöl.), a fish scale which is thin and shows concentric lines of growth, without serrations on the margin called?

cycloid — Of or pertaining to the Cycloidei. Cycloid scale (Zoöl.), a fish scale which is thin and shows concentric lines of growth, without serrations on the margin. (Webster's 1913.)

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