cy·cloid /ˈsaɪˌklɔɪd/
 擺線,輪轉線(a.)圓形的,循環性格的
 cy·cloid /ˈsaɪˌklɔɪd/ 名詞
 環狀的,圓形的,圓滾線
 Cy·cloid n.  Geom. A curve generated by a point in the plane of a circle when the circle is rolled along a straight line, keeping always in the same plane.
 Note: ☞ The common cycloid is the curve described when the generating point (p) is on the circumference of the generating circle; the curtate cycloid, when that point lies without the circumference; the prolate or inflected cycloid, when the generating point (p) lies within that circumference.
 Cy·cloid, a. Zool. Of or pertaining to the Cycloidei.
 Cycloid scale Zool., a fish scale which is thin and shows concentric lines of growth, without serrations on the margin.
 Cy·cloid, n. Zool. One of the Cycloidei.
 ◄ ►
 cycloid
      adj : resembling a circle [syn: cycloidal]
      n : a line generated by a point on a circle rolling along a
          straight line