megalith

from WordNet (r) 3.0 (2006)

megalith
    n 1: memorial consisting of a very large stone forming part of a
         prehistoric structure (especially in western Europe) [syn:
         {megalith}, {megalithic structure}]

from The Collaborative International Dictionary of English v.0.48

Megalith \Meg"a*lith\, n. [Mega- + -lith; cf. F. m['e]galithe.]
   A large stone; especially, a large stone used in constructing
   ancient monuments. -- {Meg`a*lith"ic}, a.
   [1913 Webster]

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