grampus
 oxford
 views  updated May 09 2018gram·pus  / ˈgrampəs/ •
n. (pl.  -pus·es) a cetacean of the dolphin family, in particular: ∎ another term for Risso's dolphin. ∎ another term for orca.
 The Oxford Pocket Dictionary of Current English 
   grampus
 oxford
 views  updated Jun 08 2018grampus name for several delphinoid cetaceans. XVI. Earliest forms 
graundepose, 
grampoys, alt. (by assim. to 
GRAND) of †
gra(s)peys (XIV) — OF. 
grapois, 
graspeis, also 
craspois :- medL. 
craspiscis, f. L. 
crassus fat, 
CRASS, 
piscis FISH.
  The Concise Oxford Dictionary of English Etymology T. F. HOAD