Oxford English Dictionary
etymology: French pastiche < Italian pasticcio (confused mixture, incl. pie containing pasta and meat)
A. noun. 1.a. A novel, poem, painting, etc., incorporating several different styles, or made up of parts drawn from a variety of sources.
2.a. A work, esp. of literature, created in the style of someone or something else; a work that humorously exaggerates or parodies a particular style.
b. The technique of incorporating distinctive elements of other works or styles in a literary composition, design, etc.
B. adjective. 1. Composed as an imitation or parody of a particular style or artist.
2. Exhibiting or incorporating an amalgam of different styles.