In linguistics, the syntax–semantics interface (also known as the syntax-lexical semantics interface) is the interaction between syntax and semantics. Its study encompasses phenomena that pertain to both syntax and semantics, with the goal of explaining correlations between form and meaning. Specific topics include scope, binding, and lexical semantic properties such as verbal aspect and nominal individuation, semantic macroroles, and unaccusativity.
The interface is conceived of very differently in formalist and functionalist approaches. While functionalists tend to look into semantics and pragmatics for explanations of syntactic phenomena, formalists try to limit such explanations within syntax itself. Aside from syntax, other aspects of grammar have been studied in terms of how they interact with semantics; which can be observed by the existence of terms such as morphosyntax–semantics interface.
Within functionalist approaches, research on the syntax–semantics interface has been aimed at disproving the formalist argument of the autonomy of syntax, by finding instances of semantically determined syntactic structures.
Levin and Rappaport Hovav, in their 1995 monograph, reiterated that there are some aspects of verb meaning that are relevant to syntax, and others that are not, as previously noted by Steven Pinker. Levin and Rappaport Hovav isolated such aspects focusing on the phenomenon of unaccusativity that is "semantically determined and syntactivally encoded".
Van Valin and LaPolla, in their 1997 monographic study, found that the more semantically motivated or driven a syntactic phenomena is, the more it tends to be typologically universal, that is, to show less cross-linguistic variation.
In formal semantics, semantic interpretation is viewed as a mapping from syntactic structures to denotations. There are several formal views of the syntax-semantics interface which differ in what they take to be the inputs and outputs of this mapping.