The term "string bass" is typically used to refer to a large musical instrument that is played with a bow or plucked with the fingers. However, there are several other synonyms that are often used to describe this instrument. One popular term is "double bass," which originated in the orchestral context and is still used today. Another common synonym is "upright bass," which is typically used in jazz and pop music. "Contrabass" and "bass violin" are also occasionally used to describe this instrument. Regardless of which term is used, the string bass remains a versatile and powerful instrument capable of providing a deep, resonant sound to any musical ensemble.