There are several options that depend on the definition of a "side of face".
An infinite cone
a paraboloid
a semi-hyperboloid
an ellipsoid
a spheroid are some examples.
And, last but not least, a smooth blob.
Its an Cylinder
Spherical
Sphere
A cone?
A cone.
Cone
hemisphere
A cone perhaps?
a cone
cone
cylinder
Sphere, torus, moebius strip