What part of speech is downstairs?

"Downstairs" can be a few different parts of speech, depending on its use in a sentence:

* Adverb: Describing where something is located or where an action takes place. Example: "The kids are playing downstairs."

* Noun: Referring to the lower floor of a building. Example: "I heard a noise coming from downstairs."

* Adjective: Used to describe something that is located downstairs. Example: "The downstairs bathroom needs to be cleaned."

It's important to look at the context of the sentence to determine the correct part of speech.