Immemorial
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
Beyond human memory; time out of mind.
— Immemorial possession. In Louisiana. Possession of which no man living has seen the beginning, and the existence of which he has learned from his elders. Civ. Code La. art. 762
— Immemorial usage. A practice which has existed time out of mind; custom; prescription. Miller v. Garlock, 8 Barb. (N. Y.) 154.