SERF

Agricultural worker bound by the feudal system (4)

Solution has appeared in 2 crosswords (1 across and 1 down):

• Quick crossword No 16,582 — 2023-06-28 23:00:37
  9A: Tied agricultural worker in feudal times (4)
• Quick crossword No 15,695 — 2020-08-25 23:00:07
  3D: Agricultural worker bound by the feudal system (4)