The term 'NEATENING TOOL' can be summarized by the crossword solution EDGER, which is a five-letter word. An edger is a gardening tool used to trim and neaten the edges of lawns, gardens, and other outdoor areas. It is typically a handheld device with a blade or wheel that is used to cut grass and weeds along the edges of a lawn or garden. Edgers are also used to create clean lines and borders around flower beds and other landscaping features.