Q From Phil Murphy: Can you tell me whether the words synecdoche and metonymy mean the same thing?
A Both are figures of speech used in rhetoric. They’re not the same thing, though metonymy is often interpreted so widely that synecdoche can be regarded as a special case of it.
Let’s take synecdoche first (which is pronounced as /sɪˈnɛkdəkɪ/ , by the way). You use this when you speak of a part of something but mean the whole thing. When Patrick O’Brian has Captain Jack Aubrey tell his first lieutenant to “let the hands go to dinner” he’s employing synecdoche, because he’s using a part (the hand) for the whole man. You can also reverse the whole and the part, so using a word for something when you only mean part of it. This often comes up in sport: a commentator might say that “The West Indies has lost to England” when he means that the West Indian team has lost to the English one. America is often used as synecdoche in this second sense, as the word refers to the whole continent but is frequently applied to a part of it, the USA.
Metonymy is similar, but uses something more generally or loosely associated with a concept to stand in for it. When Americans speak of the Oval Office, for example, they are really referring to the activity within it, the position or function of the President. It’s a linked term, and so a metonym. British writers refer similarly to the Crown, when they’re really discussing the powers, authority and responsibilities of the monarchy, which is symbolised by the crown. The difference between synecdoche and metonymy is that in metonymy the word you employ is linked to the concept you are really talking about, but isn’t actually a part of it. Another example is the turf for horse racing. But the distinction isn’t always obvious and often can’t be rigorously applied, and many people use metonymy to mean both.
In his story Here Lies Miss Groby, James Thurber wrote about his English teacher’s attempts to explain metonymy by talking about “the container for the thing contained”. This sounds like synecdoche rather than metonymy, but Miss Groby’s examples show she really meant metonymy. For example, when Shakespeare had Antony say in Julius Caesar: “Friends, Romans, Countrymen, lend me your ears” he was speaking figuratively of the thing the ears contained — that is, their function, their ability to listen, not some literal component. Thurber recalled that he lay awake that night trying to find an example of the reverse idea and came up with an image of an angry wife about to bash hubby over the head with a bottle of Grade A, saying “Get away from me or I’ll hit you with the milk”. That’s metonymy all right, but you can argue it’s also synecdoche, because milk is an essential component part of a bottle of milk, not just something associated with it.