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Webster 1913 Edition
Moat
Moat
,Noun.
 [OF. 
mote 
hill, dike, bank, F. motte 
clod, turf: cf. Sp. & Pg. mota 
bank or mound of earth, It. motta 
clod, LL. mota
, motta
, a hill on which a fort is built, an eminence, a dike, Prov. G. mott 
bog earth heaped up; or perh. F. motte
, and OF. mote
, are from a LL. p. p. of L. movere 
to move (see Move
). The name of moat
, properly meaning, bank or mound, was transferred to the ditch adjoining: cf. F. dike 
and ditch
.] (Fort.) 
A deep trench around the rampart of a castle or other fortified place, sometimes filled with water; a ditch. 
 Moat
,Verb.
 T.
 To surround with a moat. 
Dryden.
 Webster 1828 Edition
Moat
MOAT
,Noun.
  MOAT
,Verb.
T.