Ground-floor and Ground floor

Ground-floor adjective - On the floor closest to level with the ground.

Ground floor and ground-floor are semantically related. In some cases you can use "Ground floor" instead a noun phrase "Ground-floor".

Ground floor noun - The floor of a building that is at or nearest to the level of the ground around the building.

Ground-floor and ground floor are semantically related. Sometimes you can replace phrase "Ground-floor" with "Ground floor", this phrases are similar.