What is suffix for enormous?

There isn't a specific suffix for "enormous". The word itself is already a complete adjective, meaning "very large".

However, you could use suffixes to create related words like:

* Enormously: (adverb) meaning "to a very large extent"

* Enormousness: (noun) meaning "the quality of being enormous"

* Enormity: (noun) meaning "great wickedness or evil" (this word has a different meaning than "enormousness")

Let me know if you have any other questions!