Terrace

A flat roof with a balustrade, used as a living space.

Merriam-Webster Online Dictionary
terrace (noun)
1.
a) a colonnaded porch or promenade
b) a flat roof or open platform
c) a relatively level paved or planted area adjoining a building
2.
a) a raised embankment with the top leveled
b) one of usually a series of horizontal ridges made in a hillside to increase cultivatable land, conserve moisture, or minimize erosion
3.
a level ordinarily narrow plain usually with steep front bordering a river, lake, or sea , also a similar undersea feature
4.
a) a row of houses or apartments on raised ground or a sloping site
b) a group of row houses
c) a strip of park in the middle of a street often planted with trees or shrubs
d) - street
5.
a section of a British soccer stadium set aside for standing spectators
terrace (verb)
transitive verb
1.
to provide (as a building or hillside) with a terrace
2.
to make into a terrace