Retardando

Retardando is a tempo marking in Western classical music that instructs the performer to slow the tempo gradually. The term comes from Italian retardare, meaning "to delay" or "to slow down." In many scores, retardando is used interchangeably with ritardando; both indicate a progressive slowdown. Some editors distinguish rallentando as a broader, more gradual slackening of tempo rather than a strict, measured retardation. The exact interpretation can vary by tempo feeling and stylistic tradition.

Notation and execution: Retardando is commonly placed at the end of a passage and may be written as ritardando (rit.), retardando (ret.), or rallentando (rall.). The performer gradually reduces the pulse through the marked section, often leading to a new tempo or back to the original tempo with an a tempo marking. The degree and rate of slowing are left to interpretive discretion, guided by context, style, and ensemble tempo.

Context and related terms: Retardando is frequently used to heighten expressive effect at cadences or phrasing. It is related to rubato, which involves flexible timing within a phrase, but retardando prescribes a measurable tempo change. In practice, the terms ritardando, rallentando, and retardando are often used interchangeably, with the precise meaning shaped by period, composer, and edition.