"Megalith" means "large stone"; an antonym might be "pebble".
A megalith is a large stone that forms a prehistoric monument, such as a stone circle or chamber. Stonehenge is a well-known Megalith.
A megalith is a large stone that has been used to construct a structure or monument, either alone or together with stones.
The Collins dictionary defines megalith as a stone of great size, especially part of a prehistoric monument.
Large, old blocks of cut stone, such as those at Stonehenge.
A megalith is a large stone which has been shaped and set up. Megaliths are used in ancient monuents such as Stonehenge.
Some words that start with "mega" and refer to something large are megaphone, megaton, and megalith.
It means "huge stone" and is used in the context of large prehistoric stones erected presumably for some reigious purpose.
builders
To unlock Jet, you need to beat the Great Megalith time challenge with a 5 star ranking.
a megalith
A huge stone monument in the Stone Age is often referred to as a megalith. Examples include Stonehenge in England and the Moai statues on Easter Island.