lookout

noun7

1. •
   A session of watching for an approaching enemy, police, etc.

   • We kept a lookout all night, but nobody came.
2. •
   A person on watch for approaching enemy, police, danger, etc.

   • The raid failed when the lookout noticed the enemy group.
3. •
   A vantage point with a view of the surrounding area.
4. •
   An observation window.

   • Twenty-one of these vehicles were later converted into bogie brake vans for freight service. [...] The extreme width over the side lookouts is 9 ft. — 1941
5. •
   One's perspective, outlook; hence, one's responsibility. (used with a possessive pronoun or a noun in a possessive form).

   • Every person's interest is his own lookout.
6. •
   A subject for observation; a prospect or view.
7. •
   A joist that extends in cantilever out from the exterior wall (or wall plate) of a building, supporting the roof sheathing and providing a nailing surface for the fascia boards.