What is the meaning of mask?

noun

• A covering to disguise or conceal the face.
• Activity that tries to conceal something.
  • usage: "no mask could conceal his ignorance"; "they moved in under a mask of friendship"
• A party of guests wearing costumes and masks.
  • synonyms: masquerade, masquerade party, masque
• A protective covering worn over the face.

verb

• Hide under a false appearance.
  • usage: "He masked his disappointment"
  • synonyms: dissemble, cloak
• Put a mask on or cover with a mask.
  • usage: "Mask the children for Halloween"
• Make unrecognizable.
  • usage: "The herb masks the garlic taste"; "We disguised our faces before robbing the bank"
  • synonyms: disguise
• Cover with a sauce.
  • usage: "mask the meat"
• Shield from light.
  • synonyms: block out