IPA: /mɪˈtɒnɪmɪkəl/
KK: /mɪˈtɒnɪmɪkəl/
Relating to a figure of speech where one word or phrase is substituted for another with which it is closely associated.
The term 'the White House' is metonymical, referring to the U.S. government rather than the building itself.
Metonymical → It is formed from "metonymy" (from Greek "metōnymia", meaning a change of name) and the suffix "-ical" (meaning pertaining to). The word "metonymical" refers to something that pertains to or is characteristic of a change of name, often used in the context of language and rhetoric.
Think of 'metonymy' as a 'change of name' in language, and remember that 'metonymical' describes something related to that concept.