Definition of "synecdoche"

synecdoche

/sɪˈnɛk.də.ki/

noun
countable and uncountable, plural synecdoches
1. (rhetoric) A figure of speech that uses the name of a part of something to represent the whole, or the whole to represent a part.
  Quotations
  Synecdoche the whole for part will take,Or part for whole, just for the metre's sake.]
  Langley, A Manual of the Figures of Rhetoric, […], Doncaster: Printed by C. White, Baxter-Gate, page 9
  "Holocaust" can become a tired synecdoche for war crimes in general.
  2002 Sep, Christopher Hitchens, “Martin Amis: Lightness at Midnight”, in The Atlantic
  Perhaps being in a touring band was, to Yorke, a synecdoche for the modern condition: disorientation, alienation, rootlessness, exhaustion, lack of control, occasional derangement, constant motion.
  2017 May 17, Dorian Lynskey, “The 20-year-old black mirror that reflects the world today”, in BBC.com Culture‎
2. (rhetoric) The use of this figure of speech.