The meaning of SYNECDOCHE is a figure of speech by which a part is put for the whole (such as fifty sail for fifty ships), the whole for a part (such as society for high society), the species for the genus (such as cutthroat for assassin), the genus for the species (such as a creature for a man), or the name of the material for the thing made (such as boards for stage). Frequently Asked Questions About synecdoche . Synecdoche is a figure of speech that uses a part or a whole to refer to a related thing. Learn about the two main types of synecdoche (microcosm and macrocosm), how it differs from metaphor and metonymy, and see common examples in literature, advertising, and sports. What is the difference between synecdoche and metonymy? Synecdoche and metonymy (pronounced meh- tah -nuh-mee) are both rhetorical devices that substitute one word or phrase for another word or phrase, but they are different. Synecdoche uses a word that is a smaller part of the whole thing it’s describing (or vice versa). Synecdoche is an important figure of speech in English. It lets you use just a part to talk about the whole, or the whole to talk about a part. You’ll see it in school textbooks, exam questions, literature, and daily conversations. Understanding synecdoche improves your reading, writing, and speaking skills for both exams and real-world English.