Properly the International Load Line, a mark on the hull of a merchant ship to show the waterline under specified conditions. The line shows the maximum capacity load the ship may carry.
A line formed by the surface of the water on the hull of a ship when she is afloat; any of a series of short lines marked on the hull to show where the waterline would be under different loadings.
A line showing where the water has been, usually a line separating dry land and wet areas; a watermark or tidemark.
A horizontal line indicating the shape of an airfoil.
The inner rim of the eyelid, just behind the lash line; primarily used in reference to the application of eyeliner.