Which word describes a smooth style in music?

The word that best describes a smooth style in music is "gebunden," which translates from German to mean "bound" or "connected." In musical terms, this refers to a legato style where notes are played in a flowing manner with no separations between them, creating a smooth and connected sound. This contrasts with a more detached or staccato approach, where notes are played crisply and individually.

The other options do not effectively convey the essence of smoothness in music. "Lebhaft" suggests a lively and spirited character, emphasizing energy rather than smoothness. "In relievo" refers to a three-dimensional effect, often used in visual arts rather than music, which does not relate to the concept of smooth playing. "Legerement," while it means lightly or delicately, does not specifically capture the idea of a sustained and smooth musical line as directly as "gebunden" does.