Sometimes people learn new words, other times keeping old words (usually modified) works better. To take your example, in Turkish the word for vacuum cleaner literally translates as "electric broom", and cell phones are commonly called "cep" which actually translates as "pocket". Or consider the British who still use electric torches (that's a flashlight for all you non-Brits).
All the companies are branding as "mobile." I don't think they really even sell household corded phones anymore, we don't have to be specific about them.
If I wanted a corded phone, I think I'd have to use that specific modifier to get one.
Anyway, back to the point--say "mobile phone" to Americans and they know it's a cellular phone.
Seconded. "cellphone" and "mobile phone" are basically interchangeable to me. Though, honestly I'm more likely to just refer to it as a "phone" and use a qualifier to refer to the non-mobile variety (e.g. "house phone" or "land-line")
Nah, "hoover" is just your dialect. American here, grew up in CA, and I've never heard or said "hoover".
But yeah, I wouldn't say "vacuum" as a method of action unless you really drilled down. (Something about "pump" and "sucking", but I'd have to think for a bit to get to the actual physical "vacuum" aspect of it.)
