1. gave shelter or refuge to (a person, especially one in hiding or in need)
2. held or kept (a thought, feeling, or grudge) in the mind
3. provided a place where (something unwanted, such as disease or pests) could live or develop

Examples

• The family harboured refugees during the war.
• She harboured a deep resentment toward her former colleague.
• He harboured hopes of becoming a professional musician.
• The old building harboured rats and insects.
• They harboured doubts about the plan's success.
• The port harboured dozens of fishing vessels.