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noun \ˈmask\

Definition of mask

  1. 1 a (1) :  a cover or partial cover for the face used for disguise (2) :  a person wearing a mask :  masker b (1) :  a figure of a head worn on the stage in antiquity to identify the character and project the voice (2) :  a grotesque false face worn at carnivals or in rituals c :  an often grotesque carved head or face used as an ornament (as on a keystone) d :  a sculptured face or a copy of a face made by means of a mold

  2. 2 a :  something that serves to conceal or disguise :  pretense, cloak <aware of the masks, facades and defenses people erect to protect themselves — Kenneth Keniston> b :  something that conceals from view c :  a translucent or opaque screen to cover part of the sensitive surface in taking or printing a photograph d :  a pattern of opaque material used to shield selected areas of a surface (as of a semiconductor) in deposition or etching (as in producing an integrated circuit)

  3. 3 a :  a protective covering for the face b :  gas mask c :  a device covering the mouth and nose to facilitate inhalation d :  a comparable device to prevent exhalation of infective material e :  a cosmetic preparation for the skin of the face that produces a tightening effect as it dries

  4. 4 a :  the head or face of an animal (as a fox or dog) b :  an area (as the one around the eyes) of an animal's face that is distinguished by usually darker coloring

Examples of mask in a sentence

  1. Everyone wore costumes and masks to the dance.

  2. Doctors wear surgical masks in the operating room.

Origin and Etymology of mask

Middle French masque, from Old Italian maschera

First Known Use: 1534




Simple Definition of mask

  • : to hide (something) from sight

  • : to keep (something) from being known or noticed

Source: Merriam-Webster's Learner's Dictionary

Full Definition of mask

  1. intransitive verb
  2. 1 :  to take part in a masquerade

  3. 2 a :  to assume a mask b :  to disguise one's true character or intentions

  4. transitive verb
  5. 1 :  to provide or conceal with a mask: as a :  to conceal from view <mask a gun battery> b :  to make indistinct or imperceptible <masks undesirable flavors> c :  to cover up <masked his real purpose>

  6. 2 :  to cover for protection

  7. 3 :  to modify the size or shape of (as a photograph) by means of an opaque border


play \-ˌlīk\ adjective

Examples of mask in a sentence

  1. The house was masked by trees.

  2. They tried to mask their real purpose.

  3. She tried using perfume to mask the bad odor.

Circa 1562

First Known Use of mask

circa 1562

Synonym Discussion of mask

disguise, cloak, mask mean to alter the dress or appearance of so as to conceal the identity or true nature. disguise implies a change in appearance or behavior that misleads by presenting a different apparent identity <disguised herself as a peasant>. cloak suggests a means of hiding a movement or an intention <cloaked their maneuvers in secrecy>. mask suggests some often obvious means of hiding or disguising something <smiling to mask his discontent>.

MASK Defined for Kids



noun \ˈmask\

Definition of mask for Students

  1. 1 :  a cover for the face or part of the face used for disguise or protection <a Halloween mask> <a catcher's mask>

  2. 2 :  something that disguises or conceals <She visited under a mask of friendship.>




Definition of mask for Students



  1. :  conceal, disguise <She found it difficult to mask her anger.>

Medical Dictionary



noun \ˈmask\

Medical Definition of mask

  1. 1:  a protective covering for the face

  2. 2a:  any of various devices that cover the mouth and nose and are used to prevent inhalation of dangerous substances, to facilitate delivery of a gas (as oxygen or a general anesthetic), or to prevent the dispersal of exhaled infective material—see gas mask, oxygen mask

  3. 3:  a cosmetic preparation for the skin of the face that produces a tightening effect as it dries



transitive verb

Medical Definition of mask

  1. 1:  to prevent (an atom or group of atoms) from showing its ordinary reactions <to mask hydroxyl in a sugar by converting it into methoxyl>

  2. 2:  to modify or reduce the effect or activity of (as a process or a reaction)

  3. 3:  to make indistinct or imperceptible <flavorings used in pharmacy to mask the taste of medications>

  4. 4:  to raise the audibility threshold of (a sound) by the simultaneous presentation of another sound

Seen and Heard

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different from the usual or normal

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