3-room(ed) apartment

[kohyoongliat]

3-room apartment and 3-roomed apartment are both correct.
What I don't understand is why '3-roomed' apartment is correct since there is no such word as 'roomed'.

Thanks in advance.

[Anglika]

Merriam-Webster has "roomed" as an adjective - which would make sense in this context, where it is a modifier for "apartment".

[kohyoongliat]

So it is AmE.
Thanks, Anglika.

[Anglika]

Not really. It is used here when describing housing of any kind, and the OED gives it as an adjective as well.

[kohyoongliat]

Thanks, Anglika.

I didn't know that.

Best wishes