The title role in the performing arts is the performance part that gives the title to the piece, as in Aida, Giselle, Michael Collins, or Othello. The actor, singer, or dancer who performs that part is also said to have the title role.
The performer playing the title role is not always the lead and the title role may or may not be the protagonist. In the television miniseries Shogun, for example, Toshirō Mifune had the title role, but the lead was played by Richard Chamberlain. In the James Bond novel The Man with the Golden Gun, the title character is the primary antagonist. The title role and the lead can be different genders; for example, in the 2003 revival of August Wilson's Ma Rainey's Black Bottom, Whoopi Goldberg had the title role, but the lead was Charles S. Dutton.
The title character in narrative works is one who is named or referred to in the title, such as The Doctor in the TV series Doctor Who, Harry Potter in the series of novels and films, Romeo and Juliet in the Shakespeare play or Annie Oakley in the musical Annie Get Your Gun
The title character need not be fictional, such as Erin Brockovich in the film of that name or Thomas More in the play A Man for All Seasons by Robert Bolt.
The title character need not be named in the title, but may be referred to by some other word or phrase, such as Bilbo Baggins in The Hobbit or Idi Amin in The Last King of Scotland. A title character may only be indirectly described in the title, as in An Ideal Husband by Oscar Wilde, where the 'ideal husband' (the title role) is the apparently perfect Sir Robert Chiltern.
The title character need not be the subject of the whole title in a strict grammatical sense: Uncle Tom is the title character of Uncle Tom's Cabin and Lee Marvin is often attributed with playing the title character in the film The Man Who Shot Liberty Valance, as his character (Liberty Valance) is named in the title, even though the subject of the title is the person who shot him.
A title character may be the main antagonist, e.g. Sauron in The Lord of the Rings or Bram Stoker's Dracula. In The Wonderful Wizard of Oz, the wizard is the title character, but Dorothy Gale is the main character. In the video game The Legend of Zelda, the title character, Princess Zelda, is the damsel in distress, but the protagonist is Link. The title character may be unseen, e.g. Godot in Waiting for Godot or Jason Bourne in the 2012 film The Bourne Legacy.
Title character has been attributed to objects, for example the bus in the film and musical Priscilla, Queen of the Desert.
The general phrase "title character" can be replaced with a description of the character, which is then "titular". For example, the title character of Dracula can be referred to as "the titular vampire", and the title character of Hamlet is "the titular prince of Denmark".