chlorambucil
Concise Oxford English Dictionary © 2008 Oxford University Press:
chlorambucil /klɔːˈrambjʊsɪl/
▶noun Medicine a drug used in the treatment of cancer.
– origin 1950s: from chlor(oethyl)am(inophenyl)bu(tyric acid), the systematic name, + -cil.
'chlorambucil' also found in these Oxford entries:

