apartmentblock

As an adjective flat is

having no variations in height.

As an adverb flat is

so as to be flat.

As a noun flat is

an area of level ground or flat can be (archaic|new england|now chiefly british) an apartment.

As a verb flat is

(poker slang) to make a flat call; to call without.

As a verb terraced is

(terrace).

As an adjective terraced is

of, relating to, or being a terraced house.