im·memorial \|i(m)+\adjective Etymology: probably from French immémorial, from Middle French immemorial, from in- in- (I) + memorial — more at memorial : extending beyond the reach of memory, record, or tradition : indefinitely ancient < existing from time immemorial > < a chapel of immemorial age — Andrew Lang > < immemorial elms — Alfred Tennyson > • im·memorially\“\adverb