Dolmen and Standing stone

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

Standing stone and dolmen are semantically related. In some cases you can use "Standing stone" instead a noun "Dolmen".

Standing stone noun - A tall upright megalith; found primarily in England and northern France.

Dolmen and standing stone are semantically related. You can use "Dolmen" instead a noun phrase "Standing stone".