Cantabile is a musical term meaning literally "singable" or "songlike" (Italian). It has several meanings in different contexts. In instrumental music, it indicates a particular style of playing designed to imitate the human voice. For 18th century composers, the term is often used synonymously with "cantando" (singing), and indicates a measured tempo and flexible, legato playing. For later composers, particularly in piano music, cantabile indicates the drawing out of one particular musical line against the accompaniment (compare counterpoint).
Cantabile is used as a noun to mean the first half of a double aria, followed by a cabaletta. The cantabile movement would be slower and more free-form to contrast with the structured and generally faster cabaletta. Louis Spohr subtitled his violin concerto No. 8 "in moda d'una scena cantata," "in the manner of a sung scene"; opera arias exerted a strong influence on the "singable" cantabile melodic line in Romantic writing for stringed instruments.