moho(n = noun.object) mohorovicic discontinuity - the boundary between the Earth's crust and the underlying mantle; "the Mohorovicic discontinuity averages 5 miles down under oceans and 20 miles down under continents"
A gallinule (Notornis Mantelli) formerly inhabiting New Zealand, but now supposed to be extinct. It was incapable of flight. See Notornis. [1913 Webster]
moho, n. [Short for Mohorovicic discontinuity, from Andrija Mohorovi, a Yugoslavian geologist.].
The boundary between the earth's crust and the semiliquid mantle beneath. It varies in depth from 3 miles beneath the surface at certain points in the ocean to over 25 miles under certain parts of continents. [PJC]