Science, Tech, Math › Science Enantiomer Definition Share Flipboard Email Print MOLEKUUL/SCIENCE PHOTO LIBRARY / Getty Images Science Chemistry Chemical Laws Basics Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated March 06, 2017 An enantiomer is one of a pair of optical isomers. Examples The central carbon in serine is the chiral carbon. The amino group and hydrogen can rotate about the carbon, resulting in two enantiomers of serine, L-serine and D-serine.