Semantics is the study of reference, meaning, or truth. The term can be used to refer to subfields of several distinct disciplines, including philosophy, linguistics and computer science.

In linguistics, semantics is the subfield that studies meaning. Semantics can address meaning at the levels of words, phrases, sentences, or larger units of discourse. Two of the fundamental issues in the field of semantics are that of compositional semantics (which pertains on how smaller parts, like words, combine and interact to form the meaning of larger expressions, such as sentences) and lexical semantics (the nature of the meaning of words).

Several disciplines and approaches have contributed to the often-contentious field of semantics. One of the crucial questions which unites different approaches to linguistic semantics is that of the relationship between form and meaning. Some major contributions to the study of semantics have derived from studies in the 1980–1990s in related subjects of the syntax–semantics interface and pragmatics.

The semantic level of language interacts with other modules or levels (like syntax) in which language is traditionally divided. In linguistics, it is typical to talk in terms of "interfaces" regarding such interactions between modules or levels. For semantics, the most crucial interfaces are considered those with syntax, pragmatics, and phonology.

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