TGG meaning in Academic & Science ?

In linguistics, transformational grammar (TG) or transformational-generative grammar (TGG) is part of the theory of generative grammar, especially of natural languages. It considers grammar to be a system of rules that generate exactly those combinations of words that form grammatical sentences in a given language and involves the use of defined operations (called transformations) to produce new sentences from existing ones. The method is commonly associated with American linguist Noam Chomsky.

Transformational algebra was first introduced to general linguistics by the structural linguist Louis Hjelmslev. A modification which separated discourse and semantics from syntax was subsequently made by Zellig Harris, giving rise to what became known as transformational generative grammar. The full Hjelmslevian conception, in contrast, is incorporated into functional grammar.