Online Encyclopedia of Western Signs and Ideograms Symbols.com

Symbol 6:13

0613a

06:13 · A sign found on some nautical charts meaning no bottom reached with sounding.
    Inverted, as 0613b, the structure is used in musical notation as a sign for mezzo-staccato. Staccato passages in music have distinctive breaks between the successive tones, and "mezzo" means half, middle or mean.