平屋顶

Roof \Roof\, n. [OE. rof, AS. hr?f top, roof; akin to D. roef
cabin, Icel. hr?f a shed under which ships are built or kept;
cf. OS. hr?st roof, Goth. hr?t. Cf. {Roost}.]
1. (Arch.) The cover of any building, including the roofing
(see {Roofing}) and all the materials and construction
necessary to carry and maintain the same upon the walls or
other uprights. In the case of a building with vaulted
ceilings protected by an outer roof, some writers call the
vault the roof, and the outer protection the roof mask. It
is better, however, to consider the vault as the ceiling
only, in cases where it has farther covering.

2. That which resembles, or corresponds to, the covering or
the ceiling of a house; as, the roof of a cavern; the roof
of the mouth.

The flowery roof
Showered roses, which the morn repaired. --Milton.

3. (Mining.) The surface or bed of rock immediately overlying
a bed of coal or a flat vein.

{Bell roof}, {French roof}, etc. (Arch.) See under {Bell},
{French}, etc.

{Flat roof}. (Arch.)
(a) A roof actually horizontal and level, as in some
Oriental buildings.
(b) A roof nearly horizontal, constructed of such material
as allows the water to run off freely from a very
slight inclination.

{Roof plate}. (Arch.) See {Plate}, n., 10.