glucagon
Concise Oxford English Dictionary © 2008 Oxford University Press:
glucagon /ˈgluːkəg(ə)n, -gɒn/
▶noun Biochemistry a peptide hormone formed in the pancreas which promotes the breakdown of glycogen to glucose in the liver.
– origin 1920s: from Gk glukus ‘sweet’ + agōn ‘leading, bringing’.
'glucagon' also found in these Oxford entries:

