(1):

(n.) A surface which may be generated by a straight line moving in such a manner as always to meet a given straight line and a given curve, and continue parallel to a given plane.

(2):

(a.) Resembling a cone; conoidal.

(3):

(n.) A solid formed by the revolution of a conic section about its axis; as, a parabolic conoid, elliptic conoid, etc.; - more commonly called paraboloid, ellipsoid, etc.

(4):

(n.) Anything that has a form resembling that of a cone.