rubato

As a noun rubato

is (music) a tempo in which strict timing is relaxed, the music being played near, but not on the beat.

As an adjective undefined is

lacking a definition or value.

In music|lang=en terms the difference between rallentando and rubato

is that rallentando is (music) slackening; becoming slower (used as a musical direction) while rubato is (music) a tempo in which strict timing is relaxed, the music being played near, but not on the beat.

As an adjective rallentando

is (music) slackening; becoming slower (used as a musical direction).

As a noun rubato is

(music) a tempo in which strict timing is relaxed, the music being played near, but not on the beat.

As nouns the difference between rubato and rabato

is that rubato is a tempo in which strict timing is relaxed, the music being played near, but not on the beat while rabato is stiff collar, wired or starched, worn in the 16th and 17th centuries; sometimes used as a support for the ruff.

As nouns the difference between rebato and rubato

is that rebato is alternative form of rabato while rubato is a tempo in which strict timing is relaxed, the music being played near, but not on the beat.