lookout

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The act of observing or keeping watch.
2. n. A high place or structure commanding a wide view, used for observation.
3. n. One who keeps watch.
4. n. South Atlantic U.S. Outlook; view.
5. n. An object of concern or worry. See Synonyms at affair.

Century Dictionary and Cyclopedia

1. n. A watching for the appearance or occurrence of anything, especially from without; vigilant observation or scrutiny; watch: as, to keep a good lookout at sea; to be on the lookout for an opportunity.
2. n. A place where a watch is kept; a post of external observation: as, the lookout on a ship's mast.
3. n. A person or party engaged in keeping watch, especially for things outside.
4. n. The subject of observation or vigilance; something to be watched for or guarded against: as, every man's interest is his own lookout.
5. n. A prospect or view; an outlook.
6. n. In car-building, a glazed clearstory on the roof of a caboose, designed to enable the train-hands to obtain a clear view over the tops of the cars in a train.

Wiktionary

1. n. A vantage point with a view of the surrounding area.
2. n. A person on watch for approaching enemy, police, etc.
3. n. A subject for observation; a prospect or view.
4. n. One's perspective, outlook; hence, one's responsibility. (used with a possessive pronoun or a noun in a possessive form).

GNU Webster's 1913

1. n. A careful looking or watching for any object or event.
2. n. The place from which such observation is made.
3. n. A person engaged in watching; a sentinel; a sentry.
4. n. colloq. Object or duty of forethought and care; responsibility.

WordNet 3.0

1. v. be vigilant, be on the lookout or be careful
2. v. to protect someone's interests
3. n. the act of looking out
4. n. a person employed to keep watch for some anticipated event
5. n. an elevated post affording a wide view
6. n. a structure commanding a wide view of its surroundings