Nayru's Wisdom is a song on the Goddess's Harp in Skyward Sword. Link learns it on the Isle of Songs after finishing the Ancient Cistern and empowering the Master Sword with the Sacred Flame there. Nayru's Wisdom is used to open the Trial Gate to access Nayru's Silent Realm in Lanayru Desert, similar to how Farore's Courage and Din's Power open the Trial Gates in their respective regions. If Link successfully completes Nayru's Silent Realm, he receives the Double Clawshots.
The name of the song refers to the Goddess of Wisdom, Nayru.