Moho
Concise Oxford English Dictionary © 2008 Oxford University Press:
Moho /ˈməʊhəʊ/
▶noun Geology the boundary surface between the earth's crust and the mantle.
– origin 1930s: abbrev. of Mohorovičić discontinuity, named after the Yugoslav seismologist Andrija Mohorovičić.
'Moho' also found in these Oxford entries:

