Endocentric and exocentric

In theoretical linguistics, a distinction is made between endocentric and exocentric constructions. 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. The distinction reaches back at least to Bloomfield's work of the 1930s. Such a distinction is possible only in phrase structure grammars (constituency grammars), since in dependency grammars all constructions are necessarily endocentric. Further information about the classification of compounds please see Bisetto and Scalise. In theoretical linguistics, a distinction is made between endocentric and exocentric constructions. 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. The distinction reaches back at least to Bloomfield's work of the 1930s. Such a distinction is possible only in phrase structure grammars (constituency grammars), since in dependency grammars all constructions are necessarily endocentric. Further information about the classification of compounds please see Bisetto and Scalise. An endocentric construction consists of an obligatory head and one or more dependents, whose presence serves to modify the meaning of the head. For example: These phrases are indisputably endocentric. They are endocentric because the one word in each case carries the bulk of the semantic content and determines the grammatical category to which the whole constituent will be assigned. The phrase big house is a noun phrase in line with its part house, which is a noun. Similarly, sing songs is a verb phrase in line with its part sing, which is a verb. The same is true of very long; it is an adjective phrase in line with its part long, which is an adjective. In more formal terms, the distribution of an endocentric construction is functionally equivalent, or approaching equivalence, to one of its parts, which serves as the center, or head, of the whole. An endocentric construction is also known as a headed construction, where the head is contained 'inside' the construction. An exocentric construction consists of two or more parts, whereby the one or the other of the parts cannot be viewed as providing the bulk of the semantic content of the whole. Further, the syntactic distribution of the whole cannot be viewed as being determined by the one or the other of the parts. The classic instance of an exocentric construction is the sentence (in a phrase structure grammar). The traditional binary division of the sentence (S) into a subject noun phrase (NP) and a predicate verb phrase (VP) was exocentric: Since the whole is unlike either of its parts, it is exocentric. 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). Thus with the advent of X-bar Theory, the endocentric vs. exocentric distinction started to become less important in the theory of syntax, for without the concept of exocentricity, the notion of endocentricity was becoming vacuous. In theories of morphology however, the distinction remains, since certain compounds seem to require an exocentric analysis, e.g. have-not in Bill is a have-not. For a class of compounds described as exocentric, see bahuvrihi. The endo- vs. exocentric distinction is possible in phrase structure grammars (= constituency grammars), since they are constituency-based. The distinction is hardly present in dependency grammars, since they are dependency-based. In other words, dependency-based structures are necessarily endocentric, i.e. they are necessarily headed structures. Dependency grammars by definition were much less capable of acknowledging the types of divisions that constituency enables. Acknowledging exocentric structure necessitates that one posit more nodes in the syntactic (or morphological) structure than one has actual words or morphs in the phrase or sentence at hand. What this means is that a significant tradition in the study of syntax and grammar has been incapable from the start of acknowledging the endo- vs. exocentric distinction, a fact that has generated confusion about what should count as an endo- or exocentric structure.