Or else. Used as a direction to the performer to designate an alternate section or passage.
(music) In a musical score an ossia is an alternative version of the music, often just a few measures long.
Origin of ossia
- Italian from o sia or let it be o or (from Latin aut) sia third person sing. present subjunctive of essere to be (from Latin esse es- in Indo-European roots)
From American Heritage Dictionary of the English Language, 5th Edition