<Dd> On the fingerboard (i.e. in string playing, an indication to bow or to pluck over the fingerboard); playing over the fingerboard produces a duller, less harmonically rich, gentler tone . The opposite of sul ponticello . </Dd> <Dd>' single key'; used on a continuo part to indicate that the notes should be played without harmony </Dd> <Dd> Time (i.e. the overall speed of a piece of music) </Dd> <Dt> tempo di marcia </Dt>

What is the italian term for this mark in measure 16 what does it mean