This was the original title for Joseph Heller’s classic satirical anti-war novel Catch-22.
Catch-18
Catch-11
Catch-17
Catch-14
Catch-18. In fact, the book’s first chapter was published in New World Writing magazine in 1955 under the title of "Catch-18." The title was changed to prevent confusion with the Leon Uris’ novel Mila 18 that was published the same year. "Catch-14" "Catch-11" and "Catch-17" were all considered and rejected for various reasons before "Catch-22" was settled on.