cyanmethemoglobin

[sī′ăn-mĕt′hēmə-glō′bĭn, sī′ən-]
n.
  1. A relatively nontoxic compound of cyanide with methemoglobin, formed when methylene blue is administered in cases of cyanide poisoning.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.