sumpter

noun3

1. •
   (historical) A packhorse; a beast of burden.

   • the ancient vse of somers and sumpter horsses is in maner vtterlie relinquished — 1577
2. •
   (historical) The driver of a packhorse.

   • Persuade me rather to be slave and sumpter / To this detested groom. — 1603
3. •
   (no longer used) A pack; a burden.

   • You should have had a Sumpter , tho' 'thad cost me The laying on myself — 1626