1. a person who is legally responsible for the care of someone who cannot care for themselves, especially a child
Usage: legal
2. someone who protects or defends something

Examples

• After her parents died, her aunt became her legal guardian.
• The court appointed a guardian to manage the elderly man’s finances.
• The security guard acted as guardian of the museum’s treasures.
• She saw herself as the guardian of family traditions.
• The guardian angel watched over the sleeping child.
• He was named guardian of his younger brother at age 18.
• The park ranger serves as guardian of the wilderness area.