(1):
(a.) Relating to, or associated with, the commemoration of an event that happened a hundred years before; as, a centennial ode.
(2):
(a.) Happening once in a hundred years; as, centennial jubilee; a centennial celebration.
(3):
(a.) Lasting or aged a hundred years.
(4):
(n.) The celebration of the hundredth anniversary of any event; a centenary.