What does the word rover mean?

Usage examples for rover

  1. I heard Farrell call Rover! – Foe-Farrell by Arthur Thomas Quiller-Couch
  2. But Rover did not tell. – Bobby of Cloverfield Farm by Helen Fuller Orton
  3. Davis equipped her for the pirate service, and called her " The Rover." – The Pirates Own Book by Charles Ellms