You are in the right place to learn all the things you want to know about the basic idiom “J’ai une mémoire de poisson rouge”.
Including a complete definition of what it mean and how to use it in a dialogue with an audio example. Not to mention the cool things we sprinkled like synonym, dialogue example, slow pronunciation audio and more!
The literal meaning is:
This popular expression basically means “To have a bad memory“. But why the goldfish comparison?
Because a common cliché says they have only a few seconds of memory, which has been proven false, but the cliché remains… What an injustice!
If you want to apologize for your bad memory, use: “Désolé, j’ai une mémoire de poisson rouge” (Sorry, I have a goldfish’s memory). But if you want to taunt someone with a terrible memory, use instead: “Tu as une mémoire de poisson rouge !” (You have a goldfish memory!).
Looking for the antonym of this expression? We have it too! And it’s: “Avoir une mémoire d’éléphant” → To have an elephant’s memory.
It refers to elephants because they are known to have an excellent memory. They can travel very long distances and then remember them. They can also recognize human beings and remember years later people who mistreat them.