If your character has earned a title, you can select to display it from a drop-down menu on your character screen. Once selected, the title will be shown in front of your character's name. Here are some of the available titles currently in the game:

Special Titles
Title Note

Scarab Lord Opened the Gates of Ahn'Qiraj. One Character per realm.
Gladiator Top title for top Arena Players. Given at end of the season. (Top 0.5%)
Duelist Second highest title for top Arena Players (Top 0.5% - 3%)
Rival Third highest title for top Arena Players (Top 3% - 10%)
Challenger Lowest title for top Arena Players (Top 10 - 35%)
Justicar (A)/Conqueror (H) Exalted with Alterac Valley, Arathi Basin and Warsong Gulch factions

Arena Titles: These titles will last through the following season, and at the end of the following season they will be removed and titles will be redistributed to the new season's top teams.

PvP Ranks (Outdated)
Under the original PvP ranking system in World of Warcraft, rank titles could be earned through PvP. These rank titles can no longer be obtained with the changes to the PvP system. However, the highest rank you obtained under the old system can still be displayed.

Rank Icon Alliance Title Horde Title

14 Grand Marshal High Warlord
13 Field Marshal Warlord
12 Marshal General
11 Commander Lieutenant General
10 Lieutenant Commander Champion
9 Knight-Champion Centurion
8 Knight-Captain Legionnaire
7 Knight-Lieutenant Blood Guard
6 Knight Stone Guard
5 Sergeant Major First Sergeant
4 Master Sergeant Senior Sergeant
3 Sergeant Sergeant
2 Corporal Grunt
1 Private Scout