Synonyms for Mask:

n.

astringent, cleanser, baby oil, Aloe vera, antiperspirant, hood, calamine lotion, cream, cold-cream, costume, antiseptic, balm. hold in, protection, repress, master, manage, deal with, bottle up, keep back. submerge, blot out, tuck away, carnival, revel, lie low, party. countenance, dissimulate, expression, glare, look, grimace, eye, long face, frown. guise, front, pretext, false colors, gloss, window dressing, coloring, put on, semblance, face, color, Disguisement, pretense. blind (noun)
blindfold.
covering (noun)
coating, patina, covering, veneer, canopy, skin, envelope, shroud, wrapping, screening, casing, dermis.
mask (noun)
cloak, masquerade, masque, block out, dissemble.
masked ball (noun)
masque.
misrepresentation (noun)
false colors.

v.

conceal (verb)
bury, conceal, obscure, censor, screen, blind, hide, disguise, hush, camouflage.
cover (verb)
cloak, encase, envelop, overlay, blanket, enshroud, cover, wrap, veil, sheath, coat.
disguise (verb)
cover, hide, obscure, guard, dissimulate, shield, conceal, dissemble.

Other synonyms:

dissimulate, Gas Mask, false colors, Disguisement, window dressing, long face, blindfold, submerge. guise, semblance, pretense, countenance, grimace, face mask, frown. glare, tuck away, coloring. gloss, shield, front. expression. put on. guard. eye. look, face. conceal
tuck away, lie low.
cover
encase, enshroud, blanket.

Usage examples for mask

  1. Midnight had struck already; I told her that her good fame made it necessary for me to go away; I put my mask on and left the house. – The Memoires of Casanova, Complete The Rare Unabridged London Edition Of 1894, plus An Unpublished Chapter of History, By Arthur Symons by Jacques Casanova de Seingalt
  2. 4 P. M. The cavalry, supported by the Stonewall Brigade, was immediately placed a short distance down the plank road, in order to mask the march of the column. – Stonewall Jackson And The American Civil War by G. F. R. Henderson
  3. She may have changed her mind about not letting us know what she was going to mask as. – Marjorie Dean, College Sophomore by Pauline Lester