Cromlech and Megalithic structure

Cromlech noun - A prehistoric megalithic tomb typically having two large upright stones and a capstone.

Megalithic structure and cromlech are semantically related. In some cases you can use "Megalithic structure" instead a noun "Cromlech".

Megalithic structure noun - Memorial consisting of a very large stone forming part of a prehistoric structure (especially in western Europe).

Cromlech and megalithic structure are semantically related. Sometimes you can replace term "Cromlech" with "Megalithic structure", this terms are similar.