Etymology tree
Ancient Greek σᾰ́κκος (sắkkos)bor.
Latin saccus
Old French sac
French sacbor.
English sac
Borrowed from French sac. Doublet of saccus, sack, saco, and sakkos.
Meanings
A bag or pouch inside a plant or animal that typically contains a fluid.
(UK, historical) The privilege, formerly enjoyed by the lord of a manor, of holding courts, trying causes, and imposing fines; now used only in the phrase sac and soc or soc and sac.
But it is really the court-baron which represents the ancient assembly of the mark, while the court-leet represents the lord's jurisdiction of sac and soc, whether granted before or since the coming of William. 1876, Edward Augustus Freeman, The History of the Norman Conquest of England, page 311:
In later times, if the lord had "sac and soc,” his court had the authority of the Court Leet; if he had the view of frankpledge the suitors at his court were free from attendance at the sheriff's tourn; his court was then in all points like the hundred court, but independent of the sheriff. 1882, William White, History, gazetteer, and directory, of Lincolnshire, page 21:
The grant of “sac and soc” did not always carry with it the right to hold a court, but frequently amounted only to the privilege of receiving the forfeitures the lord's men should incur in the Hundred court, or possibly to one-third of the revenues of the Hundred and Shire, which had formerly gone to the ealdorman. 1899 February, F. M. Cobb, “Early English Courts”, in The Western Reserve Law Journal, volume 5, number 1, page 16: