Logical form (linguistics)

In generative grammar and related approaches, the logical form (LF) of a linguistic expression is the variant of its syntactic structure which undergoes semantic interpretation. It is distinguished from phonetic form, the structure which corresponds to a sentence's pronunciation. These separate representations are postulated in order to explain the ways in which an expression's meaning can be partially independent of its pronunciation, e.g. scope ambiguities.

LF is the cornerstone of the classic generative view of the syntax-semantics interface. However, it is not used in Lexical Functional Grammar and Head-Driven Phrase Structure Grammar, as well as some modern variants of the generative approach.