waterline >> ˈwɔːtəlʌɪn
Definition: [noun] the level normally reached by the water on the side of a ship.
Definition: [noun] a linear watermark in paper.
Definition: [noun] the rim of the upper or lower eyelid between the lashes and the eye itself (especially with reference to the application of eye make-up).
Example: line the waterline with the black eyeliner