S: (n) corolla ((botany) the whorl of petals of a flower that collectively form an inner floral envelope or layer of the perianth) "we cultivate the flower for its corolla"
S: (n) calyx ((botany) the whorl of sepals of a flower collectively forming the outer floral envelope or layer of the perianth enclosing and supporting the developing bud; usually green)
S: (n) hull (persistent enlarged calyx at base of e.g. a strawberry or raspberry)
S: (n) pappus (calyx composed of scales or bristles or featherlike hairs in plants of the Compositae such as thistles and dandelions)
S: (n) thistledown (pappus of a thistle consisting of silky featherlike hairs attached to the seed-like fruit of a thistle)
S: (n) spheroid, ellipsoid of revolution (a shape that is generated by rotating an ellipse around one of its axes) "it looked like a sphere but on closer examination I saw it was really a spheroid"
S: (n) sphere (a three-dimensional closed surface such that every point on the surface is equidistant from the center)
S: (n) sphere (a solid figure bounded by a spherical surface (including the space it encloses))
S: (n) shaving cream, shaving soap (toiletry consisting of a preparation of soap and fatty acids that forms a rich lather for softening the beard before shaving)
S: (n) torus, toroid (a ring-shaped surface generated by rotating a circle around an axis that does not intersect the circle)
S: (n) core, magnetic core ((computer science) a tiny ferrite toroid formerly used in a random access memory to store one bit of data; now superseded by semiconductor memories) "each core has three wires passing through it, providing the means to select and detect the contents of each bit"
S: (n) rim (the shape of a raised edge of a more or less circular object)