Crust (kr?st), n. [L. crusta: cf. OF. crouste, F. croûte; prob. akin to Gr. &unr_;&unr_;&unr_;&unr_;&unr_; ice, E. crystal, from the same root as E. crude, raw. See Raw, and cf. Custard.] 1. The hard external coat or covering of anything; the hard exterior surface or outer shell; an incrustation; as, a crust of snow.
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I have known the statute of an emperor quite hid under a crust of dross. Addison.
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Below this icy crust of conformity, the waters of infidelity lay dark and deep as ever. Prescott.
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2. (Cookery) (a) The hard exterior or surface of bread, in distinction from the soft part or crumb; or a piece of bread grown dry or hard. (b) The cover or case of a pie, in distinction from the soft contents. (c) The dough, or mass of doughy paste, cooked with a potpie; -- also called dumpling.
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Th' impenetrable crust thy teeth defies. Dryden.
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He that keeps nor crust nor crumb. Shak.
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They . . . made the crust for the venison pasty. Macaulay.
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3. (Geol.) The exterior portion of the earth, formerly universally supposed to inclose a molten interior.
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4. (Zoöl.) The shell of crabs, lobsters, etc.
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5. (Med.) A hard mass, made up of dried secretions blood, or pus, occurring upon the surface of the body.
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6. An incrustation on the interior of wine bottles, the result of the ripening of the wine; a deposit of tartar, etc. See Beeswing.
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Crust, v. i. To gather or contract into a hard crust; to become incrusted.
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The place that was burnt . . . crusted and healed. Temple.
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