In lang=en terms the difference between ritardando and allargando
is that ritardando is gradually decelerating the tempo of a piece of music, especially at the end of the piece while allargando is decreasing in tempo; getting slower.
ritardando
English
Alternative forms
* Abbreviation: rit
Adverb
(-)
(music) Gradually decelerating the tempo of a piece of music, especially at the end of the piece.
Antonyms
* accelerando
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