The term SIGN OF RANK can be solved by the word STRIPE, which is a 6 letter word. A STRIPE is a type of mark or pattern that is used to indicate rank or status. It is commonly seen in military uniforms, where the number and type of stripes on a uniform indicate the rank of the wearer. Stripes are also used in other contexts, such as in sports teams, where the captain of the team may wear a different colored STRIPE on their uniform.