architrave

The lowest part of an entablature; rests on the capitals of the columns.

Flutings also adorn the short architraves each side of the fanlight, and the abacus of the pilaster columns which is carried across a supplementary lintel in front of the lintel proper, the latter being several inches to the rear because of the deeply recessed arrangement of the door.

The moldings (or other elements) framing a door, window or other rectangular opening.

I know that one hinge of this door has parted with the woodwork. Dry rot has turned the architrave to compacted dust.