(idiomatic) To guard and protect.

A translucent design impressed on the surface of paper and visible when the paper is held to the light. / (by extension) A logo superimposed on a digital image, a television broadcast, etc.

(transitive) To mark paper with a watermark. / (transitive) To mark a datafile with a digital watermark.

The sport of riding on water skis, whilst being towed by a motorboat.

present participle of water ski

A large tank of water, in an elevated position, acting as a local reservoir; water is pumped into the tank and fed by gravity to the consumers.

One set to watch; a person who keeps guard, especially one who guards a building, or the streets of a city, by night.

A perennial European herb, Nasturtium officinale, that grows in freshwater streams; used in salads and as a garnish. / A similar plant, Nasturtium microphyllum.

A word used as a motto, as expressive of a principle, belief, or rule of action; a rallying cry.

A pipe that is a conduit for water; an essential element of plumbing. / A device for smoking, such as a hookah or bong, in which the smoke is drawn through a container of water before inhaling.