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all' ottava

American  
[ahl uh-tah-vuh, ahl-lawt-tah-vah] / ˌɑl əˈtɑ və, ˌɑl lɔtˈtɑ vɑ /

noun

Music.
  1. a direction (8va), placed above or below the staff to indicate that the passage covered is to be played one octave higher or lower respectively.


Etymology

Origin of all' ottava

1815–25; < Italian: literally, at the octave