Holy Grail
The term Holy Grail was used to described any ultimate, but elusive, goal pursued in a quest.

Upon learning about the Borg's desire for the Omega molecule in 2374, Kathryn Janeway called it the Borg's Holy Grail. ()

In 2375, Doctor Julian Bashir claimed that the Holy Grail of organ replacement would be to come up with a way to inject the patient with undifferentiated tissue that could become whatever organ is needed. ()

In the 32nd century, Cleveland Booker described Michael Burnhams gear from the 23rd century as the holy grail for antique s who loved to live in the past. ()

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