I think that the title "The Great Gatsby" is ironic. The shallow aspect of Gatsby life that could seem "great" is that he is the richest, coolest, handsomest man in the neighborhood, who drives the best and most expensive car, who lives in a mansion and throws the most banging parties. However, when involving deeper with the story, the reader dissapoints of Garsby, and realizes that Gatsby is nothing but greatness.
After learning more about Gatsby, the initial fascination with him turns into disappointment. Consequently, the “great” turns bitter since actually Gatsby’s money comes from crime. His parties, house, and material wealth don’t make him happy. He’s a moral bankrupt chasing after a married woman. And he hates his real self and has created a whole new fake persona in an attempt to live out a teenage fantasy. So that the title "The Great Gatsby" seems like a sad, shallow “greatness.”
In a way, the title of the novel is ironic. Gatsby is not even the character's real name; he is called James Gatz, and decides to change his name because he wants to reinvent himself and his life. He is also not exactly "great". He has many flaws. He values the superficial things that characterize the society at the time--money, greed, thoughtlessness.
However, he does create the illusion of being a great person living an amazing life, and that is how others perceive him. He puts on a show, and the title "The Great Gatsby" also reflects the theatrical nature of his life.
