devonian devon • devonian period · · · Info · Definitions · Characters · · devonian · · Text Latin · · Script 8 · · Length 4 · · Syllables Definitions · · · (noun) from 405 million to 345 million years ago; preponderance of fishes and appearance of amphibians and ammonites. Synonyms: Devonian, Devonian period, Age of Fishes. · · Noun Definition 1 Characters · · a latin small letter a U+0061 d latin small letter d U+0064 e latin small letter e U+0065 i latin small letter i U+0069 n latin small letter n U+006E o latin small letter o U+006F v latin small letter v U+0076