immemorial
adjective /ˌɪməˈmɔːriəl/
/ˌɪməˈmɔːriəl/
(formal or literary)- that has existed for longer than people can remember
- an immemorial tradition
- My family has lived in this area from time immemorial (= for a very long time).
Word Originearly 17th cent.: from medieval Latin immemorialis, from in- ‘not’ + memorialis ‘relating to the memory’.