live long and prosper

From Star Trek, where it is a greeting used by the Vulcan aliens.

live long and prosper

1. A greeting.

   Synonym: LLAP

   • [1984 November, Jean Lorrah, chapter 3, in The Vulcan Academy Murders (Star Trek; 20), New York, N.Y.: Pocket Books, →ISBN, page 22:

     Sarek turned to the others, now offering the Vulcan salute. "Captain Kirk, Dr. McCoy, may you live long and prosper." / "Thank you, and the same to you, Mr. Ambassador," said Kirk, managing to force his hand into the proper position.]