As high on life as you can be. Explained by Houston hip hop legend Devin the Dude in his 2004 song "2 Tha X-treme".
Cloud eleven is a philosophy explaining a possible way to live. Its basic premise, as explained by Devin, is as follows:
"Get high off life, whatever your high may be, get high to the extreme."
Used in a positive manner, living on cloud eleven can allow one to progress to the top of their game and get maximum enjoyment out of life on planet Earth.
"Cloud ten was aight but I'm damn near at eleven." - Devin the Dude.
(Friend) "Whassup man, how you livin?"
(Reply) "On cloud eleven"
Above the rest; a Utopia.
"Been floating around up here on cloud eleven," Superstar II lyrics.