8va - Musical Definition
8va - An octave higher than the written notes.
Pronounced ‘oh-TAH-va’, it is used to avoid the use of ledger lines, which can be confusing for players at extremes of range. The marking is combined with a dotted line to indicate how long it should remain in force. It is always written above the stave:
To indicate that a passage should be played an octave lower, the marking 8vb is written below the stave, again combined with a dotted line:
To indicate a passage should be played two octaves higher, the marking 15ma is used. Two octaves lower is written 15mb.
Musical examples where the term '8va' is used: