Rosin (noun)

1. A brittle, amber-colored solid substance obtained from pine tree sap and used as a lubricant, adhesive, and in the production of varnishes and soaps.
2. A substance used on the bow hair of string instruments to increase friction and produce a more powerful sound.

Origin:

From middle english "rosin" from old french "rosin".

Examples:

1. The violinist applied rosin to the bow before playing.
2. The rosin was used to make the bow grip the strings better.
3. The rosin is made by heating pine tree sap.
4. The rosin was used as an adhesive to repair the broken vase.
5. The rosin was an important ingredient in the production of varnishes and soaps.