Alphabetical Index (O)

OCTAGONAL PLAN
OCULUS
Oeil De Boeuf
OFFERTORIUM
OFFICE
OGEE
OGEE ARCH
OGEE BRACE
Ogee Moulding
OIL ENGINE
Open Air Swimming Pool
OPEN HALL
OPEN HEARTH
OPEN PEDIMENT
OPEN PLAN
OPEN TRUSS
OPEN WELL STAIRCASE
ORATORY
ORCHESTRA PIT
ORDER
ORGAN
ORGAN LOFT
ORIEL WINDOW
ORTHOSTAT
OSCILLATING STEAM ENGINE
OSSET LOOM
OUBLIETTE
OUTDOOR SWIMMING POOL
OUTER BAILEY
OUTSHOT
Outshut
OVEN
OVERMANTEL
OVERSHOT WHEEL
Overstorey
OVERTHROW
OVOLO