- antediluvian, antiquated, archaic - so extremely old as seeming to belong to an earlier period; "a ramshackle antediluvian tenement"; "antediluvian ideas"; "archaic laws"
Antonym: new (indirect, via old)
- archaic, primitive - little evolved from or characteristic of an earlier ancestral type; "archaic forms of life"; "primitive mammals"; "the okapi is a short-necked primitive cousin of the giraffe"
Antonyms: late, later (indirect, via early)