hy·per·li·pi·de·mi·a (h??p?r-l?p??-d??m?-?, -l??p?-)n. An excess of fats or lipids in the blood. Also called hyperlipemia.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.