A solid having 12 plane faces.  
A solid figure having twelve rhomb faces.  
A closed plane curve generated by a point moving in such a way that the sums of its distances from two fixed points is a constant: a plane section of a right circular cone that is a closed curve.  
The portion of a regular solid left after cutting off the upper part by a plane parallel to the base; or the portion intercepted between two planes, either parallel or inclined to each other.  
A plane figure having six sides and six angles.  
A solid having 6 octagonal faces and 8 triangular faces.  
A prism having six rectangular sides, 2 hexagonal faces.  
A plane curve generated by a point so moving that the difference of the distances from two fixed points is a constant: a curve formed by the intersection of a double right circular cone with a plane that cuts both halves of the cone.  
A polyhedron having 20 faces.  
To draw within a figure so as to touch in as many places as possible i.e.  a regular polygon inscribed in a circle.  
1:
The act of measuring : MEASUREMENT 2: Geometry applied to the computation of lengths, areas, or volumes from given dimensions or angles. 

In a slanting or sidelong direction or position; with deviation from the straight line or direct course; diagonally.  
A plane figure having eight angles and eight sides.  
A solid bounded by eight plane faces.  
A solid figure having 8 six sided faces and 6 square faces.  
A plane curve generated by a point moving so that its distance from a fixed point is equal to its distance from a fixed line: the intersection of a right circular cone with a plane parallel to an element of the cone.  
Lying or extending alongside of one another and always at the same distance apart; continuously equidistant: said of two or more lines, surfaces, or concrete things.  
A foursided rectilineal figure whose opposite sides are parallel; sometimes spec. applied to a rectangle.  
A solid prism having 6 rectangular faces, 2 being long and wide, 2 being long and thin, and 2 being short and thin.  
A figure, usually a plane rectilineal figure, having five angles and five sides.  
Situated at right angles to the plane of the horizon, or directly up or down; vertical.  
A solid figure of which the two ends are similar, equal, and parallel rectilineal figures, and the sides.  
Shaped like a quadrangle (A figure having four angles and therefore four sides) having four angles; of fourcornered base or section.  
Foursided; having a foursided base or section.  
Or a diamond like, is a figure, whose opposite sides are equal, and whose opposite angles are also equal, but it hath neither equal sides, nor right angles. An figure with 2 rhombus and 4 elongated rhombuses to form an elongated solid.  
A sixsided prism with three rhombuses at each end (rhomb  A plane figure having four equal sides and the opposite angles equal, two being acute and two obtuse).  
A polyhedron that has four faces Hexaedron  cube.  
A solid figure having 4 six sided faces and 4 triangular faces.  
A solid figure having 18 (= 3 times 6) square and 8 triangular faces.  
Absolute emptiness of space; complete absence of matter.  
The point opposite to the base of a (plane or solid) figure; the point in a curve or surface at which the axis meets it; an angular point, as of a triangle or polygon. 