centennial

centennial is an   Adverb

Definition:

[1] Relating to, or associated with, the commemoration of an event that happened a hundred years before; as, a centennial ode.

[2] Happening once in a hundred years; as, centennial jubilee; a centennial celebration.

[3] Lasting or aged a hundred years. Thet opened through long lines Of sacred ilex and centennial pines. Longfellow.

Synonyms: