Which one should you use?
While cosa hai detto? is a full sentence, in casual conversation, Italians often simply say Come? (meaning "How?") to ask someone to repeat themselves.
Is there a formal and an informal way to say it?
cosa hai detto? is an informal way to ask what someone said. For more polite or formal situations, you can use Prego? to mean "Pardon?" or use the phrases Mi scusi, può ripetere? or Potrebbe ripetere, per favore? which mean "Excuse me, could you repeat, please?" and "Could you repeat, please?" respectively.
How does it change in a sentence?
To use the polite or formal version of this question when speaking to a stranger or a superior, change hai detto to ha detto to form cosa ha detto?
Did you know?
- If you use the phrase cosa hai detto? with a heavy tone, it can sound like a confrontation rather than a simple request for clarification. It may sound as if you are accusing someone of saying something offensive.
- While Prego? is used as a polite 'Pardon?', the word prego also means 'I pray' or 'please' and is the standard response when someone says 'thank you'.
- The word cosa comes from the Latin 'causa', meaning 'reason' or 'cause'. In English, this is a linguistic relative of the word 'cause'.
Examples in context
- Scusa, cosa hai detto?Sorry, what did you say?
- Non ti ho sentito, cosa hai detto?I didn't hear you, what did you say?
Example conversation
Sofia and Alessandro are having a conversation in a noisy cafe.
- SofiaCosa hai detto?What did you say?
- AlessandroTi ho chiesto se vuoi un caffè.I asked you if you want a coffee.
- SofiaAh, sì, grazie Alessandro.Ah, yes, thanks Alessandro.
- AlessandroPrendo un espresso per te.I'll get an espresso for you.
Sources
- Word origins: Wiktionary entries cosa, detto, CC BY-SA 4.0.