n. A construction involving one or several roughly hewn stone slabs of great size.
n. A large stone used in such a construction.
the GNU version of the Collaborative International Dictionary of English
n. A large stone; especially, a large stone used in constructing ancient monuments.
The Century Dictionary and Cyclopedia
n. A great stone; specifically, a stone of great size used in constructive work or as a monument, as in ancient Cyclopean and so-called Druidic or Celtic remains.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. memorial consisting of a very large stone forming part of a prehistoric structure (especially in western Europe)
Word Usage
"Plaid Cymru should use its position in government to oppose the building of the Severn Barrage "megalith", the editor of a Welsh language green magazine has told Golwg."