One Flew Over the Cuckoo's Nest

What does the title "One Flew Over the Cuckoo's Nest" mean?

The book and film of "One flew over the Cuckoo's Nest" takes place in a lunatic asylum or "Cuckoo's Nest". 

In the nursery rhyme "one flies east, one flies west, and one flies over the cuckoo's nest". 

In the story Chief Bromden and others are totally controlled by ex-army Nurse Rached. When new arrival McMurphy arrives he doesn't allow himself to be dominated but takes on Nurse Rached in a battle of wills. He flies east and she flies west. 

McMurphy wants to help the patients, especially the chief, to recover their pride and manhood from Nurse Rached. He does this with fatal consequences. 

Any story has several levels of interpretation. At the allegorical level the story mirrors the subjugation or holding down of sections of society for the comfort of those in command. One day a revolutionary leader (Martin Luther King or Pancho Villa) will arrive and attempt to set them free no matter what the consequences.