1. (n.) 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.

2. (a.) of or pertaining to the Cycloidei.

3. (n.) One of the Cycloidei.

acerb acerbate acerbic acid acidic acidulent acidulous acrimonious ambivert angry bilious bitter burning captious carping caustic cranky cycloid cyclothyme cyclothymic dyspeptic ectomorph embittered endomorph extrovert faultfinding fiery heated hot-tempered indignant introvert irate ireful jaundiced mad melancholic mesomorph phlegmatic quick-tempered rancorous rankled ratty resentful resenting sanguine schizoid schizothyme sore sour sour-tempered soured splenetic spunky stewing syntone testy tetchy touchy vinegarish virulent waxy wrathful wrathy wroth