n.
A localized region on the surface of an antigen that is capable of eliciting an immune response and of combining with a specific antibody to counter that response.
[EPI- + Greek topos, place, spot.]
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
