To echo what has been said above: Holden misheard a line in the poem as saying “catcher in the rye” rather than “catch her eye”–that is, attract her attention. His sister Phoebe corrects him.
Holden Caulfield is mentioned by name in at least one other story, a short story published in Esquire which was included in an anthology of stories from the magazine which was published in the early 1960s. It is narrated by his brother (presumably, the one who is “prostituting himself” in Hollywood). In it he expresses his anxiety and grief in having just received word that Holden, who is serving in the military, is missing in action. IIRC, he is serving in the Air Corps in WOrld War II.
There is, of course, a time paradox here, as in The Catcher in the Rye he is apparently attending high school in the early 1950s. This is hardly unprecedented in literature, as authors are known to “reinvent” characters over time. The character Studs Lonigan was introduced in a story by James T. Farrell called Studs; in it, he dies in his mid-20s. Most of the action described in the The Studs Lonigan Trilogy–including everything which takes place in the last novel, Judgment Day, occurs when Studs is older than when he was originally said to have died.
There are brother and sister who seem an awful lot like Phoebe and Holden in one of the stories included in Nine Stories, except that they are both about six years older by this time.
As for The Catcher in the Rye and assassinations, there are conspiracy theorists who argue that numerous seemingly unrelated crimes are the work of the same vast and shadowy conspiracy, and an idea has grown up that they sometimes use the novel when training brainwashed assassins.
Mark David Chapman, who murdered John Lennon, and John Hinckley Jr., who attempted to murder Ronald Reagan, were obsessed with the novel. After shooting Lennon, Chapman pulled out his dog-eared copy of the book and read until the polic came. One of them had even considered having his name changed to Holden Caulfield. After their crimes both young men issued a manifesto in which they attempted to justify their actions. Both said that reading Catcher in the Rye had caused them to despise hypocrisy, and had given them the idea to act as they did.
Citing this coincidence, some conspiracy writers have argued that the book was somehow used in “programming” the young men to kill. According to some theorists, Hinkley’s “handlers” were also responsible for his fixation on actress Jodie Foster. (A thought which just occurred to me: in Taxi Driver–the film which is said to have obsessed Hinckley–Robert DeNiro’s character, Travis Bickel, is convinced he has a duty to protect Jodie Foster from the dangers in her life, a bit like a “catcher in the rye”).
In promoting this theory, some writers have made an analogy to The Manchurian Candidate. This novel, and the far better film which resulted from it, concern a man who is brainwashed into being an assassin by “handlers” who train him to respond to the sight of the Queen of Hearts. The two situations aren’t really very similar; in The Manchurian Candidate the man becomes a sort of hypnotized zombie whenever he happens to be shown this card; he doesn’t go around talking about it and staring at it all the time. One can also ask why an incredibly clever, invisible conspiracy couldn’t make the effort to find a second book to use.
In the film Conspiracy Theory, Mel Gibson plays a cab driver who is obsessed with conspiracies, and with the book Catcher in the Rye; he has bought dozens of copies over the years without ever reading it. Eventually he learns that his fascination with conspiracy theories comes from his supressed memories of being trained as an assassin by an evil group which conditioned him to respond to the sight of the book. (I’m not really giving away much of the plot here).