ep·i·tope (?p??-t?p?)n. A small molecular region of an antigen that binds to a particular antibody or antigen receptor on a T cell; an antigenic determinant. A single antigen can have multiple epitopes.[epi- + Greek topos, place, spot.]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.epitope (??p??t??p) n (Medicine) the site on an antigen at which a specific antibody becomes attachedCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014ep?i?tope (??p ??to?p) n. a site on an antigen at which an antibody can bind, the molecular arrangement of the site determining the specific combining antibody. Also called antigenic determinant . [1970?75; epi- + -tope