An implement for drawing, made of clay and plumbago, or of some preparation of chalk, usually sold in small prisms or cylinders.

A crayon drawing.

Combination of pigments and an oily or waxy binder. The term applied to both chalk and pastel in the seventeenth and eighteenth centuries, but the modern crayon, with its greasy characteristic, was developed in the eighteenth and early nineteenth centuries. Recipes varied and included wax, tallow, white wax from the sperm whale, soap and shellac.

an icebreaker

Crayon is an educational webbased community portal, made for students, by students. Crayon is inspired by Blackboard and others like Campus Cruiser and aims to be even easier to work with and safer.

Also a graphics thingy (thanks to Martin Petersen for this answer)

To sketch, as with a crayon; to sketch or plan.

Used by a keno player to mark numbers on a ticket. Similar to a child's crayon, but usually black.

A pencil of carbon used in producing electric light.