Noun

1. Effort or hard work, especially physical work involving repeated motion of the forearm, such as scrubbing.
   • 1879, Anthony Trollope, William Makepeace Thackeray, ch. 5,

     When we were young we used to be told, in our house at home, that "elbow-grease" was the one essential necessary to getting a tough piece of work well done. If a mahogany table was to be made to shine, it was elbow-grease that the operation needed.