Definitions
1.nounA translucent design impressed on the surface of paper and visible when the paper is held to the light.
2.noun(by extension) A logo superimposed on a digital image, a television broadcast, etc.
3.nounA value stored in a datafile to ensure its integrity, so that if the file's contents are changed then the watermark will no longer match the contents.
4.nounA mark indicating the level to which water has risen.
5.verbTo mark paper with a watermark.
6.verbTo mark a datafile with a digital watermark.