noun🔗ShareSynapsidenAny animal (including all mammals) of the class Synapsida."While dinosaurs ruled the land, synapsids, the ancestors of mammals, were evolving in the shadows. "Während Dinosaurier das Land beherrschten, entwickelten sich Synapsiden, die Vorfahren der Säugetiere, im Schatten.animalbiologyorganismChat with AIVocabulary GamePractice Reading