Definitions for: Fantasia

[n] a musical composition of a free form usually incorporating several familiar themes

Webster (1913) Definition: Fan*ta"si*a, n. [It. See Fancy.] (Mus.)
A continuous composition, not divided into what are called
movements, or governed by the ordinary rules of musical
design, but in which the author's fancy roves unrestricted by
set form.

See Also: composition, musical composition, opus, piece, piece of music