Legal document inscribed in archaic language (4)
I believe the answer is:
writ
'legal document' is the definition.
(document from a court)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for writ that I've seen before include "Legal document, usually served" , "Veteran composed" , "Legal or formal document" , "It may be served" , "Formal command of law court requiring certain action" .)