IPA: /ˈlʊkaʊt/
KK: /ˈlʊkˌaʊt/
A place or person that watches over an area to keep it safe or to observe something.
The lookout on the hill spotted the approaching ship from miles away.
Lookout → It is formed from "look" (from Old English *locian*, meaning to see or observe) and "out" (meaning away from the inside or towards the outside). The word "lookout" refers to a place or person that observes from a position outside or elevated to keep watch.
Think of someone 'seeing' ('look') from a position 'away' ('out') — that's why a lookout is someone who observes from outside.