Definition of "Eleusinian"

Drives the profane from Mystery's bolted door, / And Suilence guards the Eleusinian lore.

1791, Erasmus Darwin, The Economy of Vegetation, J. Johnson, page 89

We must remember that a number of mystery cults besides the Eleusinian were current in the early centuries of Christianity and that there was abundant literature on the telete of the Orphic mysteries and doctrines.

1961, George Emmanuel Mylonas, Eleusis and the Eleusinian Mysteries, Princeton University Press, page 288