In architecture, the top or header of a doorway; the horizontal member spanning the top of a door opening (also called a lintel).
From 'door' + 'head' (Old English 'heafod'). Doorhead is a logical compound using 'head' to describe the uppermost part of the door structure, like 'head' of a river.
The 'head' of anything is its top—doorhead, watershed, masthead—and using body parts for architecture shows how older languages thought spatially through the human body as the original reference frame.
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