beast of burden
nounUK /ˌbiːst əv ˈbɜːdn/
US /ˌbiːst əv ˈbɜːrdn/
A beast of burden is a strong animal that people use to carry heavy things.
The farmer loaded the sacks onto the beast of burden and led it to the market.
OTHER MEANINGS
2. A person who is made to do hard or unpleasant work for others.
He felt like a beast of burden, doing everyone else's chores without thanks.
3. A machine or vehicle used to transport heavy loads.
The old truck was the real beast of burden of the family business.
4. In figurative use, anything that carries a heavy responsibility or load.
The small team was the beast of burden of the whole project.