workhorse

Something, such as a machine, that performs dependably under heavy or prolonged use.

A horse that is used for labor rather than for racing or riding.

A person who works tirelessly, especially at difficult or time-consuming tasks.

A horse used primarily for work; a draft horse

Anyone or anything that does a lot of work; one who works consistently or regularly.

a horse used for plowing and hauling and other heavy labor

machine that performs dependably under heavy use