To scrob means to scrub or clean something by rubbing it hard.
Scrobbed can make people think of cleaning, hard work, and making things very clean.
Examples:
She scrobbed the floor until it was very clean.
I scrobbed the dishes until they were shiny.
The boy scrobbed the dirty wall with a brush.
He scrobbed the bathtub so hard, he fell in!
She scrobbed the floor for hours and hours.
The dog scrobbed his back on the carpet.