a geometric curve whose two branches meet in a cusp at the origin and are asymptotic to a line parallel to the y -axis. Its equation is y ²(2a – x) =x ³ where 2a is the distance between the y -axis and this line

adjective

contained between the concave sides of two intersecting curvesCompare sistroid

Word Origin for cissoid

C17: from Greek kissoeidēs, literally: ivy-shaped, from kissos ivy