Masking Common

the act of concealing the existence of something by obstructing the view of it

"the cover concealed their guns from enemy aircraft"

the blocking of one sensation resulting from the presence of another sensation

"he studied auditory masking by pure tones"

scenery used to block the audience's view of parts of the stage that should not be seen

"The crew spent hours painting fresh masking on the set to hide the messy backstage equipment from the front row."

The act by which something is masked.

"The heavy rain was masking the sound of our approach, allowing us to sneak past the guards unnoticed."