nitrogen mustard definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
any of a class of compounds similar to mustard gas, but having an amino nitrogen in place of a sulfur atom: used in the treatment of cancers, etc.
nitrogen mustard - Medical Definition
Any of various toxic blistering compounds analogous to mustard gas but containing nitrogen rather than sulfur, sometimes used to control or check the growth of neoplastic cells.