What is prefix nouns?

There's no such thing as a "prefix noun" in the traditional sense. Prefixes are parts of words that are added to the beginning of a word to modify its meaning, and they are not nouns themselves.

However, there are a few ways to interpret your question:

1. Nouns formed by adding prefixes:

* It's possible to create new nouns by adding prefixes to existing words. For example:

* "pre" + "view" = "preview" (noun)

* "un" + "do" = "undo" (noun)

* "re" + "write" = "rewrite" (noun)

These are still nouns, but they have been formed using prefixes.

2. Nouns used as prefixes:

* Less common, but sometimes a noun can be used as a prefix, creating a new word. Examples:

* "cyber" + "space" = "cyberspace" (noun)

* "mega" + "phone" = "megaphone" (noun)

* "super" + "market" = "supermarket" (noun)

In these cases, the noun ("cyber", "mega", "super") functions as a prefix, adding a specific meaning to the following word.

3. Misunderstanding of the term "prefix":

* You might have heard the term "prefix" used in a different context, like in computer science where it refers to a part of a file name that comes before the main part.

To clarify, if you are asking about a specific term or concept, please provide more context.