What is a 'Mordent' in musical terms?

A 'Mordent' is a specific ornament in music that involves the rapid alternation between a note and its lower auxiliary note, followed by a return to the original note. This often gives a decorative effect to the main note. In the context of the question, the correct answer describes this process accurately, highlighting that the ornament consists of the written note, followed by its corresponding lower note, and then returning to the written note again. This clarity in definition is essential for understanding how mordents are applied in musical composition and performance.

In contrast, the other options describe different musical concepts. The first option refers to a smooth transition, which is more characteristic of a legato passage rather than a mordent's rapid alternation. The third option speaks to a motif that is repeated, which is a different idea relating to themes rather than individual ornamentation. The fourth option addresses embellished notes but does not specify the distinctive alternating pattern that defines a mordent. Thus, understanding the specific structure of the mordent helps clarify its role as an ornament in music.