If a gerund is a noun formed from a verb, what is a verb formed from a noun?
It seems that there is not a noun to stand for a verb derived from a noun, (like gerund is a noun to stand for a noun derived from a verb). There are only adjectives. This may be because there is still some controversy surrounding the propriety of doing this. Even though it is very common, if it becomes generally accepted it can lead to some really weird words.
Back to your question. Of all the descriptions of turning a noun into a verb, I prefer a verbified noun. Even though I just discovered that my spell check does not accept that word. A good, brief discussion of this is at this link:
http://answers.yahoo.com/question/index?qid=20080419190637AAbOYh8
I don"t know of any one-word term for these verbs. I would call them denominal verbs. There are different terms used depending on the perspective. I would call the process verbalizing a noun. (Yes, I know this can mean something else as well. No matter.)
If I want to annoy curmudgeons, I call it verbing a noun, and a verbed noun.