cy·clo·ox·y·gen·ase (s??kl?-?k?s?-j?-n?s?, -n?z?)n.1. See COX-1.2. See COX-2.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.