Definition of "holy grail" []

• A distant, all-but-unobtainable ultimate goal of a person or organization. (noun)
• A difficult or near-impossible goal that would prove to be a major benefit (example: "nanotechnology is the holy grail of medicine") (noun)

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• "Gaining control of the courts generally and the Supreme Court in particular had become the holy grail for a generation of conservative activists-and not just, they insisted, because they viewed the courts as the last bastion of pro-abortion, pro-affirmative-action, pro-homosexual, pro-criminal, pro-regulation, anti-religious liberal elitism."
• "When the show was over, with the exception of a few NASA diehards calling in with poignant overtures about man's eternal quest for knowledge, the consensus was in: Sexton's campaign had stumbled onto the holy grail of campaigning – a new "hot button" – a yet untapped controversial issue that struck a nerve with voters."
• "Nevertheless, the quest to make the invisible visible—and demonstrate, in lab animals, how exposure to a particular chemical causes autoimmunity—is the holy grail of autoimmune disease and immunotoxicology research."