ars·phen·a·mine (ärs-f?n??-m?n?)n. A drug formerly used to treat syphilis, yaws, and other spirochetal infections.[ars(enic) + phen(yl) + amine.]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.arsphenamine (??s?f?n?m?n; -?mi?n) n (Pharmacology) a drug containing arsenic, formerly used in the treatment of syphilis and related infectionsCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014