The expression comes from theatre and refers to a complete or partial run of the text, without movement or blocking. It’s an exercise designed to help memorise the text, particularly the dialogues between the characters. The expression “à l’Italienne” would seem to evoke the rapidity with which Italians speak. At the Opera, a rehearsal “à l’Italienne” is a purely musical rehearsal, with no acting or blocking. The singers are often seated and it is generally the first time they rehearse with the orchestra. This rehearsal allows the conductor to adjust the balance between the different voices and the orchestra and to check that everybody knows the score and their arias.