Feudum autiquum
Defined in 1 dictionary — Black's (1910)
Black's Law Dictionary
Henry Campbell Black, M.A. · 1910
An ancient feud or fief; a fief descended to the vassal from his ancestors. 2 Bl. Comm. 212, 221. A fief which ancestors had possessed for more than four generations. Spelman; Priest v. Cummings, 20 Wend. (N. Y.) 349.
Defined under Feudum in Black's Law Dictionary.