Endocentric and exocentric

A grammatical construction (for instance, a phrase or compound) is said to be endocentric if it fulfils the same linguistic function as one of its parts, and exocentric if it does not.

[1] The distinction reaches back at least to Bloomfield's work of the 1930s,[2] who based it on terms by Pāṇini and Patañjali in Sanskrit grammar.

They are endocentric because the one word in each case carries the bulk of the semantic content and determines the syntactic category to which the whole constituent will be assigned.

In other words, since the whole is neither a noun (N) like Hannibal nor a verb phrase (VP) like destroyed Rome but rather a sentence (S), it is exocentric.

With the advent of X-bar theory in Transformational Grammar in the 1970s, this traditional exocentric division was largely abandoned and replaced by an endocentric analysis, whereby the sentence is viewed as an inflection phrase (IP), which is essentially a projection of the verb (a fact that makes the sentence a big VP in a sense).

By contrast, in constraint-based syntactic theories, such as Lexical Functional Grammar (LFG), exocentric constructions are still widely used, but with a different role.

Hence, in a constraints-based analysis of Warlpiri, an exocentric structure follows the auxiliary, dominating all of the verb, arguments and adjuncts which are not raised to the specifier position of the IP: In addition, in theories of morphology, the distinction remains, since certain compounds seem to require an exocentric analysis, e.g. have-not in Bill is a have-not.

Theories of syntax (and morphology) represent endocentric and exocentric structures using tree diagrams and specific labeling conventions.

Traditional phrase structure trees are mostly endocentric, although the initial binary division of the clause is exocentric (S → NP VP), as mentioned above, e.g.

[7] Linguists often classify compound verbs in Chinese into five types: Subject-Predicate 主謂結構 (SP), Verb-Object 述賓結構 (VO), Verb-Complement 述補結構 (VC), Coordinative 並列結構 (VV), and Endocentric 偏正結構.

The elements in spec of IP and under S can be freely moved and switch places, as position in c-structure, except for I, plays a pragmatic rather than syntactic role in a constraints-based analysis of Warlpiri sentence structure.