epimerPronunciation: /ˈɛpɪmə/Definition of epimer noun Chemistry each of two isomers with different configurations of atoms about one of several asymmetric carbon atoms present. Derivatives epimericPronunciation: /-ˈmɛrɪk/ adjective epimerismPronunciation: /ɪˈpɪm-, ɛ-/ noun epimer in other Oxford dictionaries Definition of epimer in the US English dictionary