cartogram
Concise Oxford English Dictionary © 2008 Oxford University Press:
cartogram /ˈkɑːtəgram/
▶noun a map on which statistical information is shown in diagrammatic form.
– origin C19: from Fr. cartogramme, from carte ‘map or card’ + -gramme (from Gk gramma ‘thing written’).
'cartogram' also found in these Oxford entries:

