Ordovician
Pronunciation : Or`do*vi"cian
Part of Speech : a.
Etymology : [From L. Ordovices, a Celtic people in Wales.] (Geol.)
Definition : Defn: Of or pertaining to a division of the Silurian formation, corresponding in general to the Lower Silurian of most authors, exclusive of the Cambrian. -- n.
Defn: The Ordovician formation.
Source : Webster's Unabridged Dictionary, 1913
Merriam-Webster's Everyday Language Reference Set: Includes: The Merriam-Webster Dictionary, The Merriam-Webster Thesaurus, and The Merriam-Webster Vocabulary Builder