1. Interjection: When used as a warning, "look out" is an interjection.
* Example: Look out! That car is coming!
2. Phrasal Verb: "Look out" can be a phrasal verb meaning to be careful or vigilant.
* Example: We need to look out for any suspicious activity.
3. Noun: "Lookout" can also be a noun meaning a place from which to watch or keep a lookout.
* Example: The ship had a lookout at the bow.
It's important to consider the context of the sentence to determine the correct part of speech.