Lookout

noun

1. A vantage point with a view of the surrounding area.
2. A session of watching for an approaching enemy, police, etc.

   "We kept a lookout all night, but nobody came."

3. A person on watch for approaching enemy, police, danger, etc.

   "The raid failed when the lookout noticed the enemy group."

4. A subject for observation; a prospect or view.
5. One's perspective, outlook; hence, one's responsibility. (used with a possessive pronoun or a noun in a possessive form).

   "Every man's interest is his own lookout."