Definitions of harbor:

• noun:   a place of refuge and comfort and security
• noun:   a sheltered port where ships can take on or discharge cargo
• verb:   hold back a thought or feeling about

  Example: "She is harboring a grudge against him"

• verb:   keep in one's possession; of animals
• verb:   secretly shelter (as of fugitives or criminals)
• verb:   maintain (a theory, thoughts, or feelings)

  Example: "Harbor a resentment"

• name:  A surname (rare: 1 in 100000 families; popularity rank in the U.S.: #18193)