Related Clues:

• Slave
• Drudge
• Work hard
• Work long and hard
• Struggle
• Peg away
• Grind
• Sweat
• Toil (away)
• Labor
• Spartacus, e.g.
• Ben-Hur, for one
• Serf
• Exertion
• Verdi's Aïda, e.g.