Rafter - A diagonal timber which forms the shape of a sloping roof and supports the roofing material attached to it.

Rafter Tail - The decoratively shaped end of a rafter which is visible beneath the eaves; especially associated with the bungalow style.

Revival Styles - The use of older styles in new architectural movements. Revival styles were especially popular during the mid nineteenth and early 20th centuries.

Roof Ridge - The top horizontal member of a sloping roof, against which the upper ends of the rafters are fixed (the line at which the rafters meet at the apex of the roof).

Romanesque Revival - The reuse in the second half of the nineteenth century of massive Romanesque (Roman and Byzantine) forms, characterized by the round arch.