Ritardando, Rallentando, and Allargando?

Question

Three common musical markings for gradual slowing down are ritardando, rallentando, and allargando. How do these differ from each other in interpretation and execution? For example, I was taught many moons ago that where ritardando meant to slow down gradually, rallentando meant to slow down more dramatically, but others have said that rallentando can be more gradual, still allowing for rubato and such effects. Is there a most common interpretation of these, or is it really up to the performer how it comes out? Does the execution change by the period of the music being played (e.g., a rit. in a Classical piece being more measured than the same in a Romantic one)?

Answer 1

Ritardando - Gradually getting slower to a stopping point.

Rallentando - Gradually getting slower to a slower tempo.

Allargando - Ritardando with increasing volume.

Hope this helps~!