pec·tic acid (p?k?t?k)n. Any of several transparent gelatinous acids that are insoluble in water and are formed by partial or complete hydrolysis of certain esters of pectin.[French pectique, related to pectin, from Greek p?ktikos, coagulating, from p?ktos, coagulated; see pectin.]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.pectic acid n (Elements & Compounds) a complex acid containing arabinose and galactose that occurs in ripe fruit, beets, and other vegetables. Formula: C35H50O33 Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014pec?tic ac?id n. any of several products of the hydrolysis of pectin esters. [1825?35;