monolith

A large block of stone, especially one used in architecture or sculpture.

Something, such as a column or monument, made from one large block of stone.

Something suggestive of a large block of stone, as in immovability, massiveness, or uniformity.

A single stone; by extension, any structure or object in stone formed of a single piece: it may be an independent monument standing alone, as an Egyptian obelisk, or a menhir, or any part of a structure, as a column.

A single stone, especially one of large size, shaped into a pillar, statue, or monument.