chry·san·the·mum (kr?-s?n?th?-m?m, -z?n?-)n.1. Any of various plants of the genus Chrysanthemum in the composite family, native chiefly to East Asia, several of which are widely cultivated as ornamentals for their showy radiate flower heads.2. A flower head of one of these plants.[Latin chr?santhemum, from Greek khr?santhemon, gold flower : khr?s-, khr?so-, chryso- + anthemon, flower (from anthos).]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.chrysanthemum (kr??sæn??m?m) n1. (Plants) any widely cultivated plant of the genus Chrysanthemum, esp C. morifolium of China, having brightly coloured showy flower heads: family Asteraceae (composites)2. (Plants) any other plant of the genus Chrysanthemum, such as oxeye daisy[C16: from Latin: marigold, from Greek khrusanthemon, from khrusos gold + anthemon flower]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014chry?san?the?mum (kr??sæn ?? m?m) n. 1. any cultivated variety of a composite plant, Chrysanthemummorifolium, native to China, and of related species, bearing autumn flowers in a diversity of color and size. 2. the flower of any such plant. [1570?80;