rubato

This term describes a deliberate deviation from a strict beat, allowing a musician to "steal" time from one note and "pay it back" in another. It is an expressive tool used to avoid mechanical rigidity, creating a more human, breathing quality in a performance. It is most commonly associated with Romantic-era piano music, such as the works of Chopin.

In a professional musical context, rubato is distinct from a complete change in tempo or a formal ritardando. While a ritardando is a gradual slowing down, rubato involves a fluid, elastic stretching and compressing of time that preserves the overall structural pulse of the piece.