MEANING: n nnoun: A figure of speech in which someone or something is referred to by the name of something associated.
For example, the use of the word crown to refer to monarchy.

ETYMOLOGY: From Latin metonymia, from Greek metonymia (change of name), from meta- (after, beyond) + onama (name). Ultimately from the Indo-European root no-men- (name) which also gave us name, anonymous, noun, synonym, eponym, renown, nominate, misnomer, moniker, and ignominy. Earliest documented use: 1553.

NOTES: When a part is used to refer to the whole, it is synecdoche. For example, the use of the word eyeballs to refer to viewers or website visitors. In metaphor, the substitution is based on analogy, in metonym on association.

ME TOO, AMY - I agree with you, Senator Klobuchar

MET ON MY _______ - How did you guys say you know each other?

METRONOMY - the art of naming cities