What does rosin mean in music?

The instrument

Rosin

Also: colophony

Rosin is the hardened tree resin applied to bow hair to create the friction that makes a string speak; without it the bow slides silently across the string.

Bow hair alone is too smooth to grip. Rosin makes the hair catch and release the string hundreds of times a second, the stick-slip mechanism that actually produces the sound. Dark rosin is softer and grippier, suiting cello and bass and cooler, drier climates; light rosin is harder and cleaner, suiting violin and viola and humid conditions. Bass rosin is markedly stickier than the rest.

A few strokes before playing is enough for a maintained bow. Over-rosining produces a gritty tone and a visible cloud of dust on the instrument, and the residue should be wiped off the strings and the top after every session, since it hardens and eventually damages varnish.

Bow hold: The bow hold is the way the right hand contacts the bow, a flexible, curved grip that lets the fingers absorb pressure changes rather than locking them out.
Détaché: Détaché is the basic string bowing in which each note gets its own bow stroke, changing direction between notes while the bow stays on the string.
Open string: An open string is a string played with no left-hand finger stopping it, sounding the pitch the string is tuned to.
Sound post: The sound post is a small wooden dowel wedged inside a string instrument between the top and back, transmitting vibration and holding the body under string tension.

Every term in this glossary is taught in context somewhere in Arco's curricula, on the staff, on the keyboard, and on your own fingerboard at the same time.

Browse the curriculum All 106 terms