A crosspiece over a door; a lintel.
A horizontal dividing bar in a window.
A transom window.
Any of several transverse structural members in a ship, especially at the stern; a thwart.
The flat or nearly flat stern of a boat or ship.
The horizontal beam on a cross or gallows.
(usually attributively) Items that have arrived over the transom.
They only met the deadline by working most of the night and making a transom filing.