What is the meaning for prefix flam?

There is no prefix "flam" in English. It is possible you are thinking of a different word or prefix, or you have misspelled the word.

Possible confusions:

* "flame" - This is a noun and can be used in many different contexts, but it doesn't function as a prefix.

* "flammable" - This word means easily set on fire. It doesn't have a separate prefix "flam."

If you could provide more context or the word you are trying to understand, I might be able to give you a more accurate answer.