The following terms define Building and Machine Parts
dam: barrier to water flow.
deck: horizontal structure extending from exterior wall.
door frame: casing around door front which it's hinged or hung.
doorjamb: door home cut into wall.
dovetail joint: projecting, wedge-shaped tenor that fits into mortise.
dowel: cylindrical length of wood used to fasten or hang.
downspout: vertical pipe that carries water from root to ground.
drain: pipe or titter for removal of fluid.
drip cap: molding at exterior top side of doors and windows that sheds rain.
duct: pipe or channel for passage of gas or liquid.
ductwork: system of ducts used lot heating, ventilation, or cooling.