Proper noun

1. The traditionally accepted landing site of the Mayflower settlers to America in 1620.
   • http://www.pilgrimhall.org/Rock.htm - 13k -
2. A breed of poultry.
   • "The Plymouth Rock was a popular old fashioned utility bird. It's a gorgeous looking bird — proud and beautifully feathered. It should lay a large brown egg and plenty of them — at least 200 a year and ideally 285."