Rooms and Walk-up

Rooms noun - Apartment consisting of a series of connected rooms used as a living unit (as in a hotel).

Walk-up and rooms are semantically related In some cases you can use "Walk-up" instead a noun "Rooms".

Walk-up noun - An apartment building without an elevator.

Rooms and walk-up are semantically related in apartment topic. Sometimes you can use "Rooms" instead a noun phrase "Walk-up".