Manyshapes have metaphorical names, i.e., their names aremetaphors: theseshapes are named after a most common object that has it. For example, "U-shape" is a shape that resembles the letterU, abell-shaped curve has the shape of the vertical cross section of abell, etc. These terms may variously refer to objects, theircross sections orprojections.
Tomahawk curve, with its handle and spike thickened
Some of these names are "classical terms", i.e., words ofLatin orAncient Greeketymology. Others areEnglish language constructs (although the base words may have non-English etymology). In some disciplines, where shapes of subjects in question are a very important consideration, the shape naming may be quite elaborate, see, e.g.,the taxonomy of shapes ofplantleaves inbotany.
Biconic shape, a shape in a way opposite to the hourglass: it is based on two oppositely orientedcones ortruncated cones with their bases joined; the cones are not necessarily the same
Geoid (From Greek Ge (γη) for "Earth"), the term specifically introduced to denote the approximation of the shape of theEarth, which is approximately spherical,but not exactly so
Heart shape, long been used for its varied symbolism
Hourglass shape orhourglass figure, the one that resembles anhourglass; nearly symmetric shape wide at its ends and narrow in the middle; some flat shapes may be alternatively compared to thefigure eight or hourglass
