Lyric discussion by vchamberlain 

Here's a URL to describe the origins of the phrase "cloud nine":

phrases.org.uk/meanings/on-cloud-nine.html

I recommend to everyone the version of this on the "Anthology" collection - divorced from the annoying Phil Spector production, this is one of Lennon's barest & most emotional songs. One of Lennon's greatest gifts was to take a personal experience & make it seem universal - from "I'm A Loser" to "Watching The Wheels" - & certainly the pain he felt when he was separated from Yoko at the this time in his life shines through in this song.

& of course, it's eerily appropriate after his assassination.

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