The term 'Garden Guardian' can be summarized by the crossword solution of 'GNOME'. A GNOME is a small humanoid creature that is typically found in gardens and is believed to bring good luck and protection. They are usually depicted as having a long white beard, a pointed hat, and a mischievous smile. Gnomes have been popular garden decorations since the 19th century and are often seen as a symbol of protection for gardens and homes.