D defs.my
Entry 1 sense Webster, 1913

Fantasia

/făn-tāzh'-ə/ · Fan·ta·si·a · IPA /fænˈteɪ.zi.ə/
01 n. A continuous composition, not divided into what are called movements, or governed by the ordinary rules of musical design, but in which the…
  1. 1.
    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.(Mus.)