watermark
waw ter mork
- n a line marking the level reached by a body of water
- n a distinguishing mark impressed on paper during manufacture; visible when paper is held up to the light
- The watermark in the Great Lakes depends on the weather.
- Everyone's attention turns to a tiny two-storied house where a few weeks ago a black watermark, allegedly resembling the head of Jesus, appeared.
- First, though, he runs a pager-sized black-light reader over the currency tendered by the customer, to check for the watermark that guarantees authenticity.