Goddess of Time
From Zelda Wiki.org
The Goddess of Time was first mentioned in the flashback of Majora's Mask, when Link first meets the Skull Kid atop the Clock Tower. In the flashback Zelda shows Link how to play the Song of Time. She says "The Goddess of Time is protecting you. When you play the Song of Time, she will aid you..."
Theory Warning: Be advised that the following article or section contains unconfirmed, fan-made theories or speculation.
The Goddess of Time is more than likely the Golden Goddess, Nayru, the Goddess of Wisdom and Law (and possibly by extension, Time.) In Phantom Hourglass, Ciela states that she is the spirit of Courage and Time, suggesting that Farore may be the Goddess of Time. This however, is less likely, considering that Nayru is more often attributed to the element of time, and it is not unusual for a character to represent themes of two goddesses (such as Laruto, the Zora Earth Sage of Wind Waker. The element of earth is usually attributed to Din, while water dwelling Zoras are associated with Nayru.)

