%centennial%

n. The two hundredth year or anniversary, or its celebration. [ 1913 Webster ]

a. [ L. centum a hundred + annus year. ] 1. Relating to, or associated with, the commemoration of an event that happened a hundred years before; as, a centennial ode. [ 1913 Webster ]

2. Happening once in a hundred years; as, centennial jubilee; a centennial celebration. [ 1913 Webster ]

3. Lasting or aged a hundred years. [ 1913 Webster ]

That opened through long lines
Of sacred ilex and centennial pines. Longfellow. [ 1913 Webster ]

n. The celebration of the hundredth anniversary of any event; a centenary. [ U. S. ] [ 1913 Webster ]

adv. Once in a hundred years. [ 1913 Webster ]

. Colorado; -- a nickname alluding to the fact that it was admitted to the Union in the centennial year, 1876. [ Webster 1913 Suppl. ]

a. Of or pertaining to half of a century, or a period of fifty years; as, a semicentennial commemoration. [ 1913 Webster ]