ma·le·ate (m??l?-?t?, m?-l???t)n. A salt, ester, or anion of maleic acid.[male(ic acid) + -ate.]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.maleate (?mæl??e?t) n (Elements & Compounds) any salt or ester of maleic acid[C19: from male(ic acid) + -ate1]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014mal?e?ate (?mæl i?e?t, -?t, ?me? li-) n. a salt or ester of maleic acid. [1850?55] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.