O

1. When placed over G, D, A, or E in a VIOLIN part (or the equivalent for other string instruments), the lowercase o stands for the word open and indicates that the notes so marked must be played on an OPEN STRING. 2. In a BASSO CONTINUO part, as a sign that only the bass NOTE or its OCTAVE should be used in the accompaniment to a given passage without filling in the HARMONY. 3. Placed above a note, usually in string parts, it signifies the use of HARMONICS. 4. In chord TABLATURE, a DIMINISHED FIFTH or CHORD.