1. a hollow rectangular building block made of concrete and coal cinders

Examples

• The garage was built with cinderblock walls.
• They stacked cinderblocks to create a garden border.
• The basement foundation was made of reinforced cinderblock.
• She painted the cinderblock wall white to brighten the room.
• The school’s gymnasium had exposed cinderblock construction.
• Workers laid cinderblocks with mortar between each layer.