A strapper is a strong and healthy young person, especially a young man.
The word 'strapper' makes people think of someone who is big, strong, and full of energy.
Examples:
He's a strapper, he can lift anything!
The strapper helped me carry the heavy boxes.
The big strapper ran fast.
The little cat thinks it's a strapper!
The strapper lifted the car over his head!
I wish I was a strapper and could lift a house!