The term TOOL FOR NAILS can be summarized as a HAMMER, which is a 6-letter tool used to drive nails into wood or other materials. Hammers are one of the oldest tools known to man and have been used since the Stone Age. They are typically made of metal and have a handle attached to a head with a flat surface on one side and a curved surface on the other. Hammers are used in a variety of applications, from carpentry to construction to automotive repair.