underlying (adj.)

A term used in LINGUISTICS to refer to an abstract level of REPRESENTATION of a SENTENCE postulated in order to explain the patterns encountered in the empirical DATA of a LANGUAGE. The notion of underlying representation (UR) or underlying forms is central to GENERATIVE GRAMMAR, where a stage of underlying structure is recognized in the DERIVATION of sentences. In early TRANSFORMATIONAL grammar, the underlying phrase-marker refers to the STRUCTURAL DESCRIPTION of a sentence which is the result of the PHRASE-STRUCTURE rules; this underlying string then acts as the input to the transformational rules, which thereby produce ‘derived’ phrase-markers. Later, the term DEEP STRUCTURE came to be used as a specific conception of underlying structure, in the context of Aspects of the Theory of Syntax, from which SURFACE STRUCTURES are transformationally derived. In GOVERNMENT-BINDING theory, the term D-STRUCTURE is used. The extent to which the various underlying representations of sentences have psychological reality has been and remains controversial.