A cone is a three-sided shape that's pointy at one end and round or tapered at the other. You might find cones made of paper, plastic, or even ice.
Cone-shaped objects are all around us. For example, you've probably seen traffic cones on roads and highways - they're used to direct drivers around construction zones. Ice cream shops often serve their treats in cone-shaped containers that we call ice cream cones. And if you've ever been to a Christmas tree farm or a park with tall trees, you might have noticed conical shapes at the top of some of them - these are called pinecones, and they're actually parts of certain types of evergreen trees.
How common is "cone"?
Word cone is considered uncommon in modern English. It has a balanced usage among all categories: speech, fiction, newspapers and academic texts.
Definitions
noun
(geometry) A surface of revolution formed by rotating a segment of a line around another line that intersects the first line.
(geometry) A solid of revolution formed by rotating a triangle around one of its altitudes.
(topology) A space formed by taking the direct product of a given space with a closed interval and identifying all of one end to a point.
Anything in the general shape of a cone.
(anatomy) Any of the small cone-shaped structures in the retina.
(slang) The bowl piece on a bong.
(category theory) An object V together with an arrow going from V to each object of a diagram such that for any arrow A in the diagram, the pair of arrows from V which subtend A also commute with it. (Then V can be said to be the cone’s vertex and the diagram which the cone subtends can be said to be its base.)
Example: A cone is an object (the apex) and a natural transformation from a constant functor (whose image is the apex of the cone and its identity morphism) to a diagram functor. Its components are projections from the apex to the objects of the diagram and it has a “naturality triangle” for each morphism in the diagram. (A “naturality triangle” is just a naturality square which is degenerate at its apex side.)
(computing theory) A set of formal languages with certain desirable closure properties, in particular those of the regular languages, the context-free languages and the recursively enumerable languages.
