Deadbolt：A latch used to secure a door closed, the latch being driven from the door into a receiver in the jamb or frame.
Deadbolt Spacing：The distance between the cylinder lock to the bore for the deadbolt lock.
Door Hand：The door hand is the description of which side of the door the lock-set is on and consequently, which side of the door has the hinge pins visible.
Double-Glazed：Outfitted with two panes of glass with a sealed airspace between.
Drywall Opening：A rectangular opening in a wall, usually an interior wall, prepared to the size @necessary to receive a pre-hung door assembly.
Dummy Cylinder：A lock without a latch, typically used for the passive door panel of a double door unit, so that the hardware appears equal to that used on the active panel.