Thanks to a friend of mine for recommending this term.
/??sa?z/ Show Spelled[uh–sahyz]
Etymology: Middle English assise, from Anglo-French, session, legal action, from asseer, asseoir to seat, from Vulgar Latin *assed?re, from Latin assid?re to sit beside, assist in the office of a judge
1) The meeting of feudal vassals with the king it also refers to decrees issued by the king after such meetings.
(MEDIEV-L. Medieval Terms)
2) A) Rule or regulation; B) procedure in legal actions concerning land. See darrein presentment, mort d’ancestor, Novel Disseisin, utrum; C) itinerant court in which such actions were tried. (Sayles, George O. The King’s Parliament of England, 143)
3) A rule, regulation, or law, enforced on the authority of the Crown, though with the assent of the barons, which modified or changed the customary law. By tranference the term came to be applied to legal procedures under assize law (e.g., the “assize” of novel disseisin), and eventually to the courts which entertained such actions and the justices who administered them. (Warren, W.L. Henry II, 633)
The Assize of Clarendon 1166
“The Assize of Clarendon firmly established judicial procedure regarding crimes, especially the use of the grand jury system. The Assize was also used to check the power the local magnates gained during Stephen’s anarchy by taking power away from the local courts (and hence the local magnates), returning it to the crown.”
*term definitions retrieved from Netserf’s Medieval Glossary