grammar

n. All natural languages are principled systems, and the principles governing use for a given language are collectively referred to as that language's grammar. The components of a grammar include a phonology to specify sound structures, a morphology to account for word formation, a syntax to generate phrases and sentences, and a semantics to derive meaning. Each of these components consists of a finite number of formal principles, which, paired with the set of lexical entries represented in the lexicon (vocabulary store), generate the infinite set of possible sentences in that language. The form and operation of grammatical principles are understood as being universal and part of the genetic endowment of humans.   

-EMF