watermark

(wôˈtər-märkˌ, wŏtˈər-)

1. a. A mark showing the greatest height to which water has risen.
   b. A line indicating the heights of high and low tide.
2. a. A translucent design impressed on paper during manufacture and visible when the paper is held to the light.
   b. The metal pattern that produces this design.

1. To mark (paper) with a watermark.
2. To impress (a pattern or design) as a watermark.