Following is the Wikipedia definitions for "meta":
Meta is a prefix used in English in order to indicate a concept which is an abstraction from another concept, used to complete or add to the latter.This way too abstract and hard to understand. A better definition for the word "meta" is given by Guy Steele in his OOPSLA'98 talk "Growing a Language" (video and paper), for the meaning used in programming but also for a more general meaning.
Meta means that you step back from your own place. What you used to do is now what you see. What you were is now what you act on. Verbs turn to nouns. What you used to think of as a pattern is now treated as a thing to put in the slot of an other pattern. A meta foo is a foo in whose slots you can put foos.If you carefully analyze this definition you'll find a very deep meaning and you'll probably realize what "meta" means. And also if you truly understand this definition than you probably understand the whole meta-programming stuff. So just read that definition very carefully.
