im·me·mo·ri·al 
/ˌɪməˈmorijəl/ adjective
/ˌɪməˈmorijəl/ adjective formal + literary : very old or ancient : from a time so long ago that it cannot be remembered
▪ the immemorial roots of human spirituality ▪ People have been creating art since time immemorial. [=a very long time ago] ▪ stories passed down from time immemorial
▪ the immemorial roots of human spirituality ▪ People have been creating art since time immemorial. [=a very long time ago] ▪ stories passed down from time immemorial
— im·me·mo·ri·al·ly /ˌɪməˈmorijəli/ adverb
▪ an immemorially ancient custom
/ˌɪməˈmorijəli/ adverb ▪ an immemorially ancient custom
