What is the term for the second statement of the main theme in a fugue, commonly found in the dominant key?

The term for the second statement of the main theme in a fugue, typically found in the dominant key, is referred to as the "Answer." In the context of a fugue, the Answer represents the initial theme transposed up a perfect fifth (or down a perfect fourth), which is a common practice after its original statement in the tonic key. This establishes a sense of balance and contrast within the structure of the fugue, contributing to the development of the thematic material. The Answer plays a crucial role in the exposition of the fugue, where the subject is introduced in various voices, facilitating the intricate interplay that defines this specific form of counterpoint.

In contrast, the other terms are associated with different aspects of fugue writing. The "Subject" refers to the main theme itself, which is first presented in the tonic key. The "Counter-subject" is a secondary theme that can be introduced concurrently with the Subject or Answer, often playing off the main theme. The "Exposition" is the section of the fugue in which the Subject and Answer are presented, establishing the foundational material for the rest of the composition. Understanding these definitions helps clarify the structure and function of each part of a fugue.