A line tattoo down the arm can be a meaningful design for many people, symbolizing transformation and growth. The line is also often seen as a protective force or a symbol of strength. At the same time, for some, the line can have a spiritual or protective significance. It could represent the journey of life, a connection to the universe and spirit, or a reminder of one’s loved ones. Line tattoos can mean different things to different people, so what it ultimately represents is up to the individual to decide.