ser·tra·line (sûr?tr?-l?n?)n. A drug of the SSRI class, C17H17Cl2 N, used in its hydrochloride form primarily to treat depression, obsessive-compulsive disorder, posttraumatic stress disorder, and anxiety.[ser(otonin) + (te)tra- + (naphtha)l(ene) + (am)ine.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.