Not long ago, a friend of mine was moving to Germany and looking for flats. She complained, on facebook, that the only kind of apartment to rent was Dachgeschosswohnung. I'm not great at German yet, so I let facebook translate it for me and it said that this word meant 'penthouse'. I took this to mean that she couldn't afford anywhere, as they were all luxury places and out of her budget, as this is the connotation of 'penthouse' in English.
What the word actually means is 'top floor flat', literally, and it's basically an attic. Now, while a penthouse is a top floor flat, it's not at all the same as an attic, which has a sloping roof and is small and non-luxurious, which is exactly what she meant when she made her complaint. Literal translation, yes, but a very different interpretation of the type of accommodation it refers to.