chalk

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. 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.
2. n. A piece of chalk or chalklike substance in crayon form, used for marking on a blackboard or other surface.
3. n. 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.
4. n. A mark made with chalk.
5. n. Chiefly British A score or tally.
6. v. To mark, draw, or write with chalk: chalked my name on the blackboard.
7. v. To rub or cover with chalk, as the tip of a billiard cue.
8. v. To make pale; whiten.
9. v. To treat (soil, for example) with chalk.
10. chalk up To earn or score: chalk up points.
11. chalk up To credit or ascribe: Chalk that up to experience.

Century Dictionary and Cyclopedia

1. n. In geology, a soft white rock, consisting almost entirely of carbonate of lime in a pulverulent or only slightly consolidated state, and readily soiling the fingers when handled. It is seen, when examined through the microscope, to be made up in large part of minute fragments of the shells of Foraminifera, mollusks, and echinoderms, and also of spicules of sponges. It does not exactly resemble any deep-sea deposit at present known to be in process of formation. This rock is a very important and conspicuous formation on the south coast of England (which on account of the whiteness of its cliffs is poetically styled Albion) and in the north of France. Under the city of London it has a thickness of from 600 to 800 feet. The chalk gives its name to the so-called Cretaceous formation. It is not known that there is any rock exactly resembling chalk in any other region than that of the Paris and London basins. Chalk, being a nearly pure carbonate of lime in a pulverized condition, is an article of great commercial importance, and is used in a large number of operations. For such purposes it is crushed and levigated. One of its principal uses is for whitening walls, or whitewashing. It is not used with oil, as it has no body with that vehicle; but, on account of its being very much cheaper than lead paint, it supersedes that article to a great extent. There are many names for the various preparations of chalk, as whiting, Spanish white, Paris white, etc. Chalk is not a desirable material for ordinary mortar, but it is used to some extent as one of the ingredients of hydraulic cement. See cement, 2.
2. n. A piece of prepared chalk used for marking on a dark surface.
3. n. A point scored in a game: so called from its being recorded with chalk.
4. n. An account. See to chalk up, below.
5. To rub or mark with chalk.
6. To manure with chalk.
7. Figuratively, to make chalky-white; blanch; make pale.
8. To mark; trace out; describe: from the use of chalk in marking lines.
9. In Scotland, to mark the door of a burgh tenant with chalk, an old mode of notice to quit, which is still competent.
10. n. In geological nomenclature the term chalk has been employed with a variety of meanings. In the English subdivisions of the Cretaceous system the Chalk constitutes the upper part of this system, resting on the Galt and Greensand, which in turn lies on the basal division or Wealden. The Chalk is divided into Lower Chalk, including the Chalk marl and the Gray Chalk of Folkestone;

Wiktionary

1. n. uncountable A soft, white, powdery limestone.
2. n. countable A piece of chalk, or, more often, processed compressed chalk, that is used for drawing and for writing on a blackboard.
3. n. Tailor's chalk.
4. n. uncountable, climbing A white powdery substance used to prevent hands slipping from holds when climbing, sometimes but not always limestone-chalk.
5. n. US, military, countable A platoon-sized group of airborne soldiers.
6. n. US, sports The prediction that there will be no upsets, and the favored competitor will win.
7. v. To apply chalk to anything, such as the tip of a billiards cue.
8. v. To record something, as on a blackboard, using chalk.
9. v. To use powdered chalk to mark the lines on a playing field.
10. v. figuratively To record a score or event, as if on a chalkboard.

GNU Webster's 1913

1. n. (Min.) A soft, earthy substance, of a white, grayish, or yellowish white color, consisting of calcium carbonate, and having the same composition as common limestone.
2. n. (Fine Arts) Finely prepared chalk, used as a drawing implement; also, by extension, a compound, as of clay and black lead, or the like, used in the same manner. See Crayon.
3. v. To rub or mark with chalk.
4. v. To manure with chalk, as land.
5. v. To make white, as with chalk; to make pale; to bleach.

WordNet 3.0

1. n. a pure flat white with little reflectance
2. n. a soft whitish calcite
3. n. a piece of calcite or a similar substance, usually in the shape of a crayon, that is used to write or draw on blackboards or other flat surfaces
4. n. an amphetamine derivative (trade name Methedrine) used in the form of crystalline hydrochloride; used as a stimulant to the nervous system and as an appetite suppressant
5. v. write, draw, or trace with chalk