Wordnet 3.0
NOUN (1)
1. 
 the boundary between the Earth's crust and the underlying mantle; 
- Example: "the Mohorovicic discontinuity averages 5 miles down under oceans and 20 miles down under continents"[syn: Mohorovicic discontinuity, Moho]
The Collaborative International Dictionary of English v.0.48:
Mohorovicic discontinuity \Mohorovicic discontinuity\, n.
   (Geol.)
   same as 2nd Moho.
   [PJC]
WordNet (r) 3.0 (2006):
Mohorovicic discontinuity
    n 1: 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" [syn:
         Mohorovicic discontinuity, Moho]