Operator (linguistics)

In generative grammar, the technical term operator denotes a type of expression that enters into an a-bar movement dependency. One often says that the operator "binds a variable".

Operators are often determiners, such as interrogatives ('which', 'who', 'when', etc.), or quantifiers ('every', 'some', 'most', 'no'), but adverbs such as sentential negation ('not') have also been treated as operators. It is also common within generative grammar to hypothesise phonetically empty operators whenever a clause type or construction exhibits symptoms of the presence of an a-bar movement dependency, such as sensitivity to extraction islands.