What's the Celtic symbol for strength and courage? The Dara Knot is the most notable symbols for strength and courage. The Dara Knot is an intricate type of knot that resembles a tree. The Irish word 'doire' means 'oak tree', and the knot shows both the tree and the root system. Trees were very significant in Celtic life and oaks were considered especially sacred. It represents wisdom, strength, power, and leadership. The Dara Celtic knot is available in a variety of ways but is generally meant to symbolize the root system of the oak tree. It is a modern creation that many view as a more complex and ornate version of the quaternary knot.