ac·ar·bose (?k?är-b?s?)n. A drug, C25H43NO18, that reduces blood glucose levels by inhibiting the breakdown of complex carbohydrates in the intestine and is used to treat type 2 diabetes.[a- + carb(o)- + -ose.]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.acarbose (e??k??b??s) na type of diabetes medicine taken orally to slow and reduce the supply of glucose to the blood.Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014