Missippian period mis·sip·pian·period uncommon noun 1. from 345 million to 310 million years ago; increase of land areas; primitive ammonites; winged insects SynonymsMississippianMissippian periodLower CarboniferousLower Carboniferous period Related words Broader terms period Parts Carboniferous WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
