Gravestone and Slab

Gravestone noun - A shaped stone laid over or erected near a grave and usually bearing an inscription to identify and preserve the memory of the deceased.

Slab and gravestone are semantically related. in memorial topic. In some cases you can use "Slab" instead a noun "Gravestone".

Slab noun - Block consisting of a thick piece of something.

Gravestone and slab are semantically related. Sometimes you can use "Gravestone" instead a noun "Slab".