A soft compact calcite, CaCO3, with varying amounts of silica, quartz, feldspar, or other mineral impurities, generally gray-white or yellow-white and derived chiefly from fossil seashells.
A piece of chalk or chalklike substance in crayon form, used for marking on a blackboard or other surface.
Games A small cube of chalk used in rubbing the tip of a billiard or pool cue to increase its friction with the cue ball.
A mark made with chalk.
Chiefly British A score or tally.
tr.v.
chalked, chalk·ing, chalks
To mark, draw, or write with chalk: chalked my name on the blackboard.
To rub or cover with chalk, as the tip of a billiard cue.
To make pale; whiten.
To treat (soil, for example) with chalk.
Phrasal Verb(s): chalk up
To earn or score: chalk up points.
To credit or ascribe: Chalk that up to experience.
[Middle English, from Old English cealk, from Latin calx, calc-, lime; see calx.] chalk'i·ness n., chalk'y adj.
[chaw-kee] 
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