This was the name of the hero of 'The Hobbit' (1937) by J. R. R. Tolkien. His real hobbit name was Bilba, which is of unknown meaning, but this was altered by Tolkien in order to use the more masculine o ending. In the novel Bilbo Baggins was recruited by the wizard Gandalf to join the quest to retake Mount Erebor from the dragon Smaug.