chlo·ram·phen·i·col (klôr??m-f?n??-kôl?, -k?l?, -k?l?)n. A broad-spectrum antibiotic, C11H12Cl2N2O5, derived from the soil bacterium Streptomyces venezuelae or produced synthetically.[chlor(o)- + am(ide) + phe(no)- + ni(tro)- + (gly)col.]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.chloramphenicol (?kl??ræm?f?n??k?l) n (Pharmacology) a broad-spectrum antibiotic used esp in treating typhoid fever and rickettsial infections: obtained from the bacterium Streptomyces venezuelae or synthesized. Formula: C11H12N2O5Cl2[C20: from chloro- + am(ido)- + phe(no)- + ni(tro)- + (gly)col]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014chlo?ram?phen?i?col (?kl?r æm?f?n ??k?l, -?k?l, ?klo?r-) n. an antibiotic obtained from cultures of Streptomyces venezuelae or synthesized, used chiefly for treating rickettsial infections. [1945?50; chlor- + am(ido)- + phe(n)- + ni(tro)- + (gly)col] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.