It's the one thing no one wants to hear muttered over the tannoy of a train station or airport: guasto.
It means 'fault', 'failure' or 'breakdown', and it's what innumerable delays are blamed upon.
Il volo Roma-Barcellona viene cancellato a causa di un guasto tecnico…
The Rome to Barcelona flight is cancelled because of a technical problem…
It's not only planes and trains that don't work. Guasto can be an adjective ('faulty') as well as a noun, and it can describe anything from machinery to people.
Il mio televisore è guasto.
My TV is broken.
If you approach a toilet door and find 'Guasto' scrawled there, you'd better find an alternative: it means 'out of order'.
And if someone warns you that the apple (mela) you're about to bite into is guasta, put it down: it's 'rotten'. Mind you, the same goes for your molars.
Ho un dente guasto.
I've got a rotten tooth.
In fact, the word derives from the verb guastare, 'to spoil, go bad, damage or ruin'.
It's enough to put anyone in a bad mood. The word for that? You guessed it: guasto. In Italian slang, it's sometimes used to mean 'fed up'.
Do you have a favourite Italian word, phrase or expression you'd like us to feature? If so, please email our editor Jessica Phelan with your suggestion.