Which musical term is used to describe a repeated rhythmic figure or melodic idea?

The term "motif" refers to a short, recurring idea that can either be a rhythmic figure or a melodic idea. In music, motifs serve as building blocks for larger compositions, allowing composers to create unity and familiarity throughout the piece. Because motifs are typically brief, they can easily be repeated and developed in various ways, making them integral to the structure and thematic material of a work.

In contrast, a theme generally refers to a longer, more complete musical idea that serves as the primary subject of a piece, whereas a variation indicates a modified form of a theme that explores different aspects, such as rhythm, harmony, or orchestration. Lastly, a fugue is a specific type of contrapuntal composition based on the systematic interweaving of melodic lines, rather than focusing on a single repeated idea.