#1 masking n. [cover, covering, screening] the act of concealing the existence of something by obstructing the view of it; "the cover concealed their guns from enemy aircraft". wn
#2 masking n. the blocking of one sensation resulting from the presence of another sensation; "he studied auditory masking by pure tones". wn
#3 masking n. [masking piece] scenery used to block the audience's view of parts of the stage that should not be seen. wn
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