noun Download 🔗Share One of a pair of stereoisomers that is the mirror image of the other, but may not be superimposed on this other stereoisomer. Almost always, a pair of enantiomers contain at least one chiral center, and a sample of either enantiomer will be optically active. Examples : "The drug ibuprofen exists as two enantiomers, but only one of them effectively reduces pain. " chemistry biochemistry compound science Chat with AIVocabulary GamePractice Reading