from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A very large stone used in various prehistoric architectures or monumental styles, notably in western Europe during the second millennium B.C.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A construction involving one or several roughly hewn stone slabs of great size.
- n. A large stone used in such a construction.
from the GNU version of the Collaborative International Dictionary of English
- n. A large stone; especially, a large stone used in constructing ancient monuments.
from 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.
from 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)
From mega- + -lith. (Wiktionary)