ˈmasking tape noun [uncountable] long narrow paper that is sticky on one side, used especially to protect the edge of an area which you are painting
[TahlilGaran] Dictionary of Contemporary English ▲
masking tape n. A paper tape that is stuck around the edges of a surface being painted to keep the paint off the surface next to it.
The painters put masking tape around the window frames to keep the paint off the glass. [TahlilGaran] English Idioms Dictionary ▲