pennsylvanian period Pennsylvanian • penny · · · Info · Definitions · Characters · · pennsylvanian period · · Text Common · · Latin · · Scripts 20 · · Length 7 · · Syllables Definitions · · · (noun) from 310 million to 280 million years ago; warm climate; swampy land. Synonyms: Pennsylvanian, Pennsylvanian period, Upper Carboniferous, Upper Carboniferous period. · · Noun Definition 1 Characters · · space U+0020 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 l latin small letter l U+006C n latin small letter n U+006E o latin small letter o U+006F p latin small letter p U+0070 r latin small letter r U+0072 s latin small letter s U+0073 v latin small letter v U+0076 y latin small letter y U+0079