tu·bo·cu·ra·rine (to?o?b?-ko?o-rä?r?n, -r?n?, -kyo?o-, tyo?o?-)n.1. An alkaloid that is an active component of curare obtained from the plant Chondrodendron tomentosum.2. The hydrated chloride form of this alkaloid, C38H44Cl2N2O6, used as a drug to relax skeletal muscles during anesthesia.[Latin tubus, tube (from the practice of shipping it in bamboo tubes) + curarine (curare + -ine).]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.tubocurarine (?tju?b??kj??r??ri?n) na toxic alkaloid obtained from the stem of a S American vine. Formula: C37H42Cl2N2O6 Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014tu?bo?cu?ra?rine (?tu bo? ky??r?r in, -?n, ?tyu-) n. the principal active alkaloid of curare, C38H44Cl2N2O, used as a muscle relaxant, esp. as an adjunct to anesthesia. [1895?1900;