Chalk vs. Gypsum

Chalknoun

(uncountable) A soft, white, powdery limestone.

Chalknoun

(countable) A piece of chalk, or nowadays processed compressed gypsum, that is used for drawing and for writing on a blackboard.

Chalknoun

Tailor's chalk.

Chalknoun

A white powdery substance used to prevent hands slipping from holds when climbing, sometimes but not always limestone-chalk.

Chalknoun

A platoon-sized group of airborne soldiers.

Chalknoun

The prediction that there will be no upsets, and the favored competitor will win.

Chalkverb

To apply chalk to anything, such as the tip of a billiard cue.

Chalkverb

To record something, as on a blackboard, using chalk.

Chalkverb

To use powdered chalk to mark the lines on a playing field.

Chalkverb

(figuratively) To record a score or event, as if on a chalkboard.

Chalkverb

To manure (land) with chalk.

Chalkverb

To make white, as if with chalk; to make pale; to bleach.

Chalknoun

A soft, earthy substance, of a white, grayish, or yellowish white color, consisting of calcium carbonate, and having the same composition as common limestone.

Chalknoun

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.

Chalkverb

To rub or mark with chalk.

Chalkverb

To manure with chalk, as land.

Chalkverb

To make white, as with chalk; to make pale; to bleach.

Chalknoun

a soft whitish calcite

Chalknoun

a pure flat white with little reflectance

Chalknoun

amphetamine used in the form of a crystalline hydrochloride; used as a stimulant to the nervous system and as an appetite suppressant

Chalknoun

a piece of chalk (or similar substance) used for writing on blackboards or other surfaces

Chalkverb

write, draw, or trace with chalk

Chalknoun

a white soft earthy limestone (calcium carbonate) formed from the skeletal remains of sea creatures.

Chalknoun

a substance (calcium sulphate) that is similar to chalk, made into white or coloured sticks for writing or drawing.

Chalknoun

a series of strata consisting mainly of chalk.

Chalknoun

short for French chalk

Chalkverb

write or draw with chalk

Chalkverb

draw or write on (a surface) with chalk

Chalkverb

rub the tip of (a snooker cue) with chalk.

Chalkverb

charge (drinks bought in a pub or bar) to a person's account

Chalk

Chalk is a soft, white, porous, sedimentary carbonate rock, a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton which had fallen to the sea floor. Chalk is common throughout Western Europe, where deposits underlie parts of France, and steep cliffs are often seen where they meet the sea in places such as the Dover cliffs on the Kent coast of the English Channel.

Gypsumnoun

A mineral consisting of hydrated calcium sulphate. When calcined, it forms plaster of Paris.

Gypsumnoun

A mineral consisting of the hydrous sulphate of lime (calcium). When calcined, it forms plaster of Paris. Selenite is a transparent, crystalline variety; alabaster, a fine, white, massive variety.

Gypsumnoun

a common white or colorless mineral (hydrated calcium sulphate) used to make cements and plasters (especially plaster of Paris)

Gypsum

Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard/sidewalk chalk, and drywall. A massive fine-grained white or lightly tinted variety of gypsum, called alabaster, has been used for sculpture by many cultures including Ancient Egypt, Mesopotamia, Ancient Rome, the Byzantine Empire, and the Nottingham alabasters of Medieval England.