mar·gin·ate (mär?j?-n?t?)tr.v. mar·gin·at·ed, mar·gin·at·ing, mar·gin·ates 1. To provide with or be a margin to; border.2. To add margin to (a stock portfolio).adj. marginate (-n?t, -n?t) also mar·gin·at·ed (-n??t?d) Biology Having a distinct border or edge.mar?gin·a?tion n.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.marginate (?m??d???ne?t) vb (tr) to provide with a margin or marginsadj (Biology) biology having a margin of a distinct colour or form: marginate leaves. [C18: from Latin margin?re] ?margin?ation nCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014mar?gin?ate (?m?r d???ne?t) adj., v. -at?ed, -at?ing. adj. 1. Biol. having a border of a distinct color. v.t. 2. to furnish with a margin; border. Also, mar?gin?at`ed.[1600?10;