What does the musical term arco mean?

In musical notation, the term "arco" means to use the bow when playing a string instrument. It is the opposite of pizzicato, which means to pluck the string with the fingers. Arco is indicated by a small curved line above or below the staff, or by the letters "arco" written in full.

When a player sees the arco marking, they will switch to using the bow to play the notes. The arco marking can be used to indicate a change of technique within a phrase or passage, or it can be used to indicate the beginning of a new section.

Arco is an important part of string playing, and it is important for players to develop a good arco technique. This involves learning how to hold the bow correctly, how to use the right amount of pressure, and how to produce a clear and consistent sound.