Synonyms for Archaic (same or very similar meaning)
WordNet sense 1 (so extremely old as seeming to belong to an earlier period):
antediluvian, antiquatedWordNet sense 2 (little evolved from or characteristic of an earlier ancestral type):
primitiveWordNet sense 3 (being or occurring at an early stage of development):
earlyFrom the ODE community, based on WordNetadd/edit