1. Greek Mythology One of a family of giants, the children of Uranus and Gaea, who sought to rule heaven and were overthrown and supplanted by the family of Zeus.
2. titan One of prodigious size, strength, or achievement: "the twin titans of the beverage industry" (David Barboza).
3. A satellite of Saturn.
[Middle English, Helios, from Latin Tītān, from Greek.]