A sledgehammer is a large, heavy hammer with a long handle, used for breaking things like rocks or walls.
A sledgehammer can make people think of hard work, construction, or demolition.
Examples:
The worker used a sledgehammer to break the wall.
I need a sledgehammer to break this rock.
The sledgehammer is too heavy for me to lift.
He used a sledgehammer to crack a nut, but it was too much.
He swung the sledgehammer with all his might, but the wall didn't budge.
The sledgehammer made a big hole in the ground when he swung it.