Writ; summons (8)
I believe the answer is:
subpoena
I believe this is a double definition.
'writ' is the first definition.
(subpoena is a kind of writ)
'summons' is the second definition.
(I've seen this before)
(Other definitions for subpoena that I've seen before include "Writ ordering someone to attend a court" , "Writ commanding appearance in court" , "Writ to compel a witness to attend court" , "Writ ordering court apperarance about bean soup" , ""Under penalty" (Latin)" .)