Definition of pièce de circonstance in US English:

pièce de circonstance

noun

  • A literary work, theory, etc., originating in or inspired by particular events or circumstances.

Origin

Mid 19th century; earliest use found in Sydney Morgan (bap. 1783, d. 1859), novelist and socialite. From French pièce de circonstance from pièce + de + circonstance.