watch

A portable or wearable timepiece.

“More people today carry a watch on their wrists than in their pockets.”

The act of guarding and observing someone or something.

A particular time period when guarding is kept.

“The second watch of the night began at midnight.”

A person or group of people who guard.

“The watch stopped the travelers at the city gates.”

The post or office of a watchman; also, the place where a watchman is posted, or where a guard is kept.

A group of sailors and officers aboard a ship or shore station with a common period of duty: starboard watch, port watch.

A period of time on duty, usually four hours in length; the officers and crew who tend the working of a vessel during the same watch. (FM 55–501).

The act of seeing, or viewing, for a period of time.

To look at, see, or view for a period of time.

“I'm tired of watching TV.”

To observe over a period of time; to notice or pay attention.

“Put a little baking soda in some vinegar and watch what happens.”

To mind, attend, or guard.

“He has to watch the kids that afternoon.”

To be wary or cautious of.

“You should watch that guy. He has a reputation for lying.”

To attend to dangers to or regarding.

“Watch what you say.”

To remain awake with a sick or dying person; to maintain a vigil.

To be vigilant or on one's guard.

“For some must watch, while some must sleep: So runs the world away.”

To act as a lookout.

(of a buoy) To serve the purpose of a watchman by floating properly in its place.

To be awake.

To be on the lookout for; to wait for expectantly.