devonian Meaning, Definition & Usage

  1. noun from 405 million to 345 million years ago; preponderance of fishes and appearance of amphibians and ammonites
    Age of Fishes; Devonian period.

WordNet

De*vo"ni*an adjective
Definitions
  1. (Geol.) Of or pertaining to Devon or Devonshire in England; as, the Devonian rocks, period, or system.
De*vo"ni*an noun
Definitions
  1. The Devonian age or formation.

Webster 1913