Main Entry: ¹wa·ter·mark

Pronunciation: \ˈwȯ-tər-ˌmärk, ˈwä-\

Function: noun

Date: 1640

1 : a mark indicating the height to which water has risen
2 : a marking in paper resulting from differences in thickness usually produced by pressure of a projecting design in the mold or on a processing roll and visible when the paper is held up to the light; also : the design of or the metal pattern producing the marking