crust

Outermost solid part of the Earth, essentially composed of a range of igneous and metamorphic rock types. In continental regions, the crust is made up chiefly of granitic rock, whereas the composition of the ocean floor corresponds mainly to that of basalt and gabbro. On average, the crust extends 22 mi (35 km) downward from the surface to the underlying mantle, from which it is separated by the Mohorovicic discontinuity (the Moho). The crust and top layer of the mantle together form the lithosphere.

crust

1. Geology the solid outer shell of the earth, with an average thickness of 30--35 km in continental regions and 5 km beneath the oceans, forming the upper part of the lithosphere and lying immediately above the mantle, from which it is separated by the Mohorovicić discontinuity

2. the dry covering of a skin sore or lesion; scab

3. Oenology a layer of acid potassium tartrate deposited by some wine, esp port, on the inside of the bottle

4. Biology the hard outer layer of such organisms as lichens and crustaceans

crust [krəst]

(geology)

The outermost solid layer of the earth, mostly consisting of crystalline rock and extending no more than a few miles from the surface to the Mohorovičić discontinuity. Also known as earth crust.

(hydrology)

A hard layer of snow lying on top of a soft layer.

Crust

in plants, a complex of tissues on the surface of the stem and roots of woody plants, consisting of dead peridermal cells and parts of the bark. The crust forms as layers of periderm repeatedly form in the phloem. In the case of more or less concentric arrangement of peridermal layers, a ringed crust forms (as in mock orange and grapes); if the peridermal layers overlap, a scaly crust forms (as in oak). Depending on the nature of the depositing of crust, it falls from the surface of the tree in layers, ribbons, or scales. Crust usually forms late (in birch, pine, and oak when the tree is 25–35 years old); it protects the plant from excessive evaporation, sharp fluctuations of temperature, and other undesirable effects.

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No references found	The jackdaws were eating pie- crust, and the magpie was drinking gravy out of a patty-pan. The Original Peter Rabbit Books by Potter, Beatrix View in context It is my own crust of bread that I eat; and though that crust is but a poor one, and sometimes actually a maggoty one, it has at least been EARNED, and therefore, is being put to a right and lawful use. Poor Folk by Dostoyevsky, Fyodor View in context The emphasis was helped by the speaker's hair, which bristled on the skirts of his bald head, a plantation of firs to keep the wind from its shining surface, all covered with knobs, like the crust of a plum pie, as if the head had scarcely warehouse-room for the hard facts stored inside. Hard Times by Dickens, Charles View in context	crush conglomerate crush fold crush injury crush kidney crush plate crush syndrome crush zone crush-forming crush-room crushed gravel crushed rock crushed steel crushed stone Crusher crusher-run aggregate crusher-run base Crushing Crushing and pulverizing crushing mill crushing strain crushing strength crushing test Crusius, Christian August Crusoe processor Crusoe, Robinson Crust crust vegetation Crustacea crustacean crustacyanin crustal motion crustal plate crustecdysone crustose crutch crutch house crutter Cruveilhier, Jean Crux Cruyff, Johan Cruz, Celia Cruz, Juan de la Cruz, Juana Inés de la Cruz, Ramón de la Cruz, Ramon Francisco de la Cruz, Ramón Francisco de la Cruz, Sor Juana Ines de la Cruz, Sor Juana Inés de la Crv cry cry of blood	crushing strength crushing strength crushing strength crushing test crushing wound crushingly crushingly crushingly crushingly crushingly crushproof crushproof crushproof crushproof crushproof crushproof crusie Crusier Crusier crusies Crusification Crusification Crusification Crusius, Christian August CRUSO Crusoe Crusoe Crusoe processor Crusoe processor Crusoe, Robinson Crust Crust (geology) Crust (geology) Crust formation Crust formation Crust formation Crust formation crust vegetation Crusta Crusta crusta lactea crusta lactea Crusta petrosa Crusta petrosa Crusta petrosa Crustacea Crustacea Crustacea Crustacea crustacean crustacean crustacean crustacean Crustacean Erythrophore Concentrating Hormone Crustacean Hyperglycemic Hormone Crustacean Louse Crustacean Louse Crustacean Louse Crustacean Shell Crustaceans Crustaceans

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The jackdaws were eating pie- crust, and the magpie was drinking gravy out of a patty-pan.

The Original Peter Rabbit Books by Potter, Beatrix View in context

It is my own crust of bread that I eat; and though that crust is but a poor one, and sometimes actually a maggoty one, it has at least been EARNED, and therefore, is being put to a right and lawful use.

Poor Folk by Dostoyevsky, Fyodor View in context

The emphasis was helped by the speaker's hair, which bristled on the skirts of his bald head, a plantation of firs to keep the wind from its shining surface, all covered with knobs, like the crust of a plum pie, as if the head had scarcely warehouse-room for the hard facts stored inside.

Hard Times by Dickens, Charles View in context

Crust playV2('en/US/sg/sgdgsgsysssthr');playV2('en/UK/sg/sgdgsgsysssthr')

crust

Crust