Blizzard trademarks "Cataclysm"

On Jun 30, Blizzard trademarked the word "Cataclysm."
What does it mean? Below is taken from Wowwiki:

"The Great Sundering, also known as simply the Sundering or the Cataclysm,WRPG 185, 211 was a world event which reshaped AzerothWar of the Ancients. This event was triggered due to the Well of Eternity being destroyed. approximately 10,000 years ago at the end of the Prior to the Sundering, there was only one continent on Azeroth, referred to as Kalimdor. In the catastrophic explosion, eighty percent of the land mass was destroyed,W3Man #? leaving behind the major continents and scattered islands that are known today: Northrend, Kezan, the Eastern Kingdoms, and the remnant still referred to as Kalimdor.
The site of the Well of Eternity became a swirling vortex of power known as the Maelstrom."


I found out through WoW.com, so read more here.