Capriccio

A title used by various 19th-century composers, among them Mendelssohn, Brahms, and Paganini, for short pieces of a capricious character.  They are usually in ternary form.

It also appears as a title of "potpourris" and "fantasias" (e.g. Saint-Saens, "Caprice sur les airs de ballet d'Alceste do Gluck").

In the 17th century, it is one of the four important prefugal forms (see Ricercar, Canzona, Fantasia).  The capriccio, as the name suggests, is less restrained than the others and frequently involves certain peculiarities.

The term also occurs as a noncommittal title of 16th- and 17th-century publications, often vocal.