ceph·a·lo·spo·rin (s?f-?-l?-spôr??n)n. Any of various beta-lactam antibiotics, derived from the fungus Acremonium chrysogenum or made semisynthetically, used to treat a wide range of bacterial infections.[New Latin Cephalosporium, former genus name (cephalo- + spora, spore; see spore) + -in.]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.cephalosporin (?s?f?l???sp??r?n) n (Pharmacology) any of a group of broad-spectrum antibiotics obtained from fungi of the genus CephalosporiumCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014ceph?a?lo?spo?rin (?s?f ? lo??sp?r ?n, -?spo?r-) n. any of a group of widely used broad-spectrum antibiotics, derived from the fungus Cephalosporium acremonium. [1950?55;