Wool-sack
Defined in 2 dictionaries — Ballentine's (1916), Black's (1910)
Ballentine's Law Dictionary
James A. Ballentine · 1916
The lord chancellor’s seat in the house of lords.
Black's Law Dictionary
Henry Campbell Black, M.A. · 1910
The seat of the lord chancellor of England in the house of lords, being a large square bag of wool, without back or arms, covered with red cloth. Webster; Brande.