What is not a noun?

This is a bit of a trick question! It depends on what you mean by "not a noun".

Here are some possibilities:

* A word that is not a noun by definition: This could be a verb, adjective, adverb, pronoun, preposition, conjunction, interjection, or even a determiner. For example:

* Run: (verb)

* Happy: (adjective)

* Quickly: (adverb)

* She: (pronoun)

* Under: (preposition)

* And: (conjunction)

* Wow!: (interjection)

* The: (determiner)

* A word that is not being used as a noun in a particular sentence: Nouns can sometimes be used as other parts of speech. For example:

* "I am going to the store." (store is a noun)

* "I need to store these items." (store is a verb)

Let me know if you have a specific word in mind! I can help you figure out what part of speech it is.