View synonyms for crust


[ kruhst ]


  1. the brown, hard outer portion or surface of a loaf or slice of bread ( crumb ).
  2. a slice of bread from the end of a loaf, consisting chiefly of this.
  3. the pastry covering the outside of a pie or other dish.
  4. a piece of stale bread.
  5. any more or less hard external covering or coating:

    a crust of snow.

  6. Geology. the outer layer of the earth, about 22 miles (35 km) deep under the continents continental crust and 6 miles (10 km) deep under the oceans oceanic crust. Compare mantle ( def 3 ), core 1( def 10 ).
  7. a scab or eschar.
  8. Slang. unabashed self-assertiveness; nerve; gall:

    He had a lot of crust going to the party without an invitation.

  9. deposit from wine, as it ripens during aging, on the interior of bottles, consisting of tartar and coloring matter.
  10. the hard outer shell or covering of an animal.
  11. Australian Slang. a living or livelihood:

    What do you do for a crust?

verb (used with object)

  1. to cover with or as with a crust; encrust.
  2. to form (something) into a crust.

verb (used without object)

  1. to form or contract a crust.
  2. to form into a crust.


/ krʌst /


    1. the hard outer part of bread
    2. a piece of bread consisting mainly of this
  1. the baked shell of a pie, tart, etc
  2. any hard or stiff outer covering or surface

    a crust of ice

  3. 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 Mohorovičić discontinuity See also sial sima
  4. the dry covering of a skin sore or lesion; scab
  5. a layer of acid potassium tartrate deposited by some wine, esp port, on the inside of the bottle
  6. the hard outer layer of such organisms as lichens and crustaceans
  7. slang.
  8. slang.
    a living (esp in the phrase earn a crust )


  1. to cover with or acquire a crust
  2. to form or be formed into a crust


/ krŭst /

  1. The solid, outermost layer of the Earth, lying above the mantle.
  2. ◆ The crust that includes continents is called continental crust and is about 35.4 to 70 km (22 to 43.4 mi) thick. It consists mostly of rocks, such as granites and granodiorites, that are rich in silica and aluminum, with minor amounts of iron, magnesium, calcium, sodium, and potassium.
  3. ◆ The crust that includes ocean floors is called oceanic crust and is about 4.8 to 9.7 km (3 to 6 mi) thick. It has a similar composition to that of continental crust, but has higher concentrations of iron, magnesium, and calcium and is denser than continental crust. The predominant type of rock in oceanic crust is basalt.


  1. In geology , the outermost layer of the Earth . It overlies the mantle .

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The crust includes the continents and the ocean bottom and is generally estimated to be about five to twenty-five miles thick.
The crust is made from relatively lightweight rocks that floated to the surface when the Earth was molten early in its history.

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Other Words From

  • crust·less adjective
  • in·ter·crust verb (used with object)
  • un·der·crust noun

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Word History and Origins

Origin of crust1

First recorded in 1275–1325; Middle English, from Anglo-French, Old French cruste, croste, from Latin crusta “hard coating, crust”

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Word History and Origins

Origin of crust1

C14: from Latin crūsta hard surface, rind, shell

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Idioms and Phrases

see upper crust .

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Example Sentences

Some of the carbon eventually returns to the surface, via erupting volcanoes or as diamonds, while some gets sequestered away in the deep crust or upper mantle.

It can cut through thick, thin, and deep-dish crusts with ease while being gentle on your wrist.

That is what lies beyond the outer crust of Kate Raworth’s doughnut.

The study highlights how seismologists are increasingly acknowledging the importance of fluids in the crust, Shelly says.

In the first scenario, the flare of energy remains anchored to the crust of the star via magnetic field lines.

Cover crust with parchment paper and pour in baking beans or weights.

Kanye refuses to stomach any rejection, no matter how upper crust.

It has French ingredients like leeks and tarragon, and I use puff pastry to make the crust easy!

Note: The egg wash both affixes the pastry to the dish and makes a lovely browned crust.

This chicken features a thin, abundant crust with so many facets and angles you want to call it rococo.

A very little crust thrown to the very hungry is always accepted with gratitude.

To demonstrate them, a crust or a hair from the affected area is softened with a few drops of 20 per cent.

A crust of bread and clear air are far preferable to luxuries enveloped in clouds of smoke and heaps of filth.

These layers form what is termed the crust of the earth, and are altogether several miles in thickness.

She holds her knife in her right hand, and in the other a crust of bread with her toothsome morsel on it.


Related Words

Definitions and idiom definitions from Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.