n. 1 false face, domino She wore a mask, and I don't know who she was 2 disguise, guise, camouflage, show, semblance, pretence, cover, cover-up, false colours, false flag, concealment, cloak, façade, veil He wormed his way into her confidence under the mask of friendship
v. 3 disguise, camouflage, cover (up), conceal, hide, obscure, veil, screen, shroud She was unable to mask her true feelings for him