Which term refers to a peculiar expression or regional dialect, such as "keep tabs on her"?

The correct answer is "idiom" because an idiom is a phrase or expression whose meaning cannot be understood from the literal meanings of its individual words. In the case of "keep tabs on her," the phrase conveys a specific idea of monitoring or keeping a close watch on someone, which differs from the literal understanding of the words "keep," "tabs," and "on." Idioms are often culturally specific and can vary significantly from one region to another, reflecting a unique aspect of a particular language or dialect.

The other options represent distinct concepts that do not align with the definition of an idiom. A cliché refers to an overused phrase or idea that has lost its originality and impact. An allusion is a reference to a well-known person, event, or piece of literature, which is not what "keep tabs on her" represents. Finally, a parody is a humorous or satirical imitation of a particular style or genre, which also does not apply to the expression in question.