File:The Diet Pill Epidemic

Description
Meta (from the Greek preposition and prefix meta- (μετά-) meaning "after", or "beyond") is a prefix used in English to indicate a concept which is an abstraction behind another concept, used to complete or add to the latter.

Any subject can be said to have a metatheory, a theoretical consideration of its properties, such as its foundations, methods, form and utility, on a higher level of abstraction. In linguistics, a grammar is considered as being expressed in a metalanguage, language operating on a higher level to describe properties of the plain language (and not itself).