bracketing (n.)

A technique used in LINGUISTICS to display the internal (HIERARCHICAL) structure of a STRING OF ELEMENTS, in a similar manner to that used in mathematics and symbolic logic. In the SENTENCE The cat saw the king, for example, the various intuitively motivated divisions it is possible to make are each associated with the imposition of a pair of brackets on to the sentence, e.g. distinguishing the cat from the king would lead to the representation [the cat] [saw] [the king]. Each pair of brackets may be associated with a label which indicates the GRAMMATICAL reason for their presence (a labelled bracketing); for example:

In a more sophisticated analysis, the order in which the pairs of brackets are applied is also made explicit, as in PHRASE-STRUCTURE GRAMMAR (here illustrated without labelling), for example:

It is plain that, as sentences become more complex, the sets of brackets within brackets will become increasingly difficult to read. The TREE diagram display is the most widely used convention to overcome this difficulty.

(2) Many of the abbreviating conventions used in writing a grammar involve brackets. In GENERATIVE grammar, the following kinds of brackets are widely used to conflate RULES:

)a) parenthesis notation (round brackets) ( ) encloses OPTIONAL elements, e.g. a rule involving D(Adj)N refers to the potential occurrence of two STRUCTURES, DN and D Adj N;

(b) brace notation (curly brackets) { } encloses alternative elements, e.g. a rule involving  refers to the selection of only one of the two structures, either D Adj N or DNN. In other approaches these brackets are used to indicate MORPHEMES, or MORPHOPHONEMIC forms;

(c) bracket notation [ ] requires that elements be matched along the same horizontal row, e.g.  reads that ‘A becomes C’ and ‘B becomes D’;

(d) angled brackets notation < > signals an interdependency between optional features in generative PHONOLOGY, e.g.  reads that ‘feature A becomes feature C, and if feature B is present it becomes feature D’. In other approaches these brackets may be used to indicate GRAPHEMES or a piece of deleted material (e.g. feb<rua>ry).

(3) In PHONETICS, there are two main uses of brackets: square brackets enclose a SEGMENTAL phonetic TRANSCRIPTION or a DISTINCTIVE FEATURE notation (e.g. [+grave]); slashes // enclose PHONEMIC transcription.

(4) Square brackets are also used to enclose FEATURES at a GRAMMATICAL or SEMANTIC LEVEL, e.g. [+common], [−countable], [+male], [−female].