The architrave (also called epistyle or door frame) is a moulded or ornamental band framing a rectangular opening.cite book
first =Francis D.K.
title =A Visual Dictionary of Architecture
publisher =John Wiley & Sons, Inc.
location =New York
pages =p. 179, 186
isbn = 0-471-edrftgyhujikolp] It is the lintel or beam that rests on the capitals of the
columns. As such, it is the lowest part of the entablatureconsisting of architrave, friezeand cornice. The word is derived from the Greek and Latin words "arche" and "trabs" combined together to mean "main beam". [cite book | author=Roth, Leland M | title=Understanding Architecture: Its Elements History and Meaning | location=Oxford, UK | publisher=Westview Press | year=1993 | id=ISBN 0-06-430158-3|page=520]
The architrave is different in the different orders. In the Tuscan, it only consists of a plain face, crowned with a fillet, and is half a module in height. In the Doric and composite, it has two faces, or fasciae; and three in the Ionic and Corinthian, in which it is 10/12 of a module high, though but half a module in the rest. 
The word architrave is also used to refer to the mouldings (or other elements) framing a door, window or other rectangular opening. See also
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