com·e·do·gen·ic (k?m??-d?-j?n??k)adj. Tending to produce or aggravate acne.[comedo + -genic.]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.comedogenic (?k?m?d??d??n?k) adjproducing or causing blackheads or acneCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014