l-: Abbreviation for levorotatory, applied to a chemical compound, as in l-dopa. Levorotary is opposed to dextrorotary which is abbreviated as d-. From the Latin laevus, on the left-hand side. SLIDESHOW Heart Disease: Causes of a Heart Attack See Slideshow From Healthy Resources 10 Rheumatoid Arthritis SymptomsWhat Is Exocrine Pancreatic Insufficiency?Common Health Conditions Among Minorities Featured Centers Good and Bad Foods for PsoriasisVideo: Getting Personal on Life With MS Health Solutions From Our Sponsors Shot-Free MS Treatment Your Child and COVID-19