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mask (măsk)
1. A covering worn on the face to conceal one's identity, as:
a. A covering, as of cloth, that has openings for the eyes, entirely or partly conceals the face, and is worn especially at a masquerade ball.
b. A grotesque or comical representation of a face, worn especially to frighten or amuse, as at Halloween.
c. A facial covering worn for ritual.
d. A figure of a head worn by actors in Greek and Roman drama to identify a character or trait and to amplify the voice.
a. A protective covering for the face or head.
b. A gas mask.
c. A usually rubber frame forming a watertight seal around the eyes and nose and containing a transparent covering for use in seeing underwater.
d. A covering for the nose and mouth that is used for inhaling oxygen or an anesthetic.
e. A covering worn over the nose and mouth, as by a surgeon or dentist, to prevent infection.
a. A mold of a person's face, often made after death.
b. An often grotesque representation of a head and face, used for ornamentation.
a. An area of contrasting color on the face and usually across the eyes of an animal.
b. The head, face, or muzzle of certain animals, such as a fox or a dog.
5. A face having a blank, fixed, or enigmatic expression.
6. Something, often a trait, that disguises or conceals: "If ever I saw misery under a mask, it was on her face" (Erskine Childers).
7. A natural or artificial feature of terrain that conceals and protects military forces or installations.
a. An opaque border or pattern placed between a source of light and a photosensitive surface to prevent exposure of specified portions of the surface.
b. The translucent border framing a television picture tube and screen.
9. Computers A pattern of characters, bits, or bytes used to control the elimination or retention of another pattern of characters, bits, or bytes.
10. A cosmetic preparation that is applied to the face and allowed to dry before being removed, used especially for cleansing and tightening the skin.
11. Variant of masque.
12. A person wearing a mask.
v. masked, mask·ing, masks
1. To cover (the face, for example) with a decorative or protective mask.
a. To cover in order to conceal, protect, or disguise: masked the baseboard with tape before painting the wall.
b. To make indistinct or difficult to perceive: spices that mask the strong flavor of the meat; sounds that were masked by white noise.
c. To conceal by dissembling: a smile that masked his anger. See Synonyms at disguise.
3. Chemistry To prevent (an atom or a group of atoms) from taking part in a normal reaction.
1. To put on a mask, especially for a masquerade ball.
2. To conceal one's real personality, emotion, or intention.

[French masque, from Italian maschera, from a source akin to Latin masca, evil spirit, specter; see MASCOT, and probably partly also from Arabic masara, laughingstock, masquerade (from saira to laugh (at), mock; see šr in the Appendix of Semitic roots).]

maska·ble adj.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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