Holy Grail noun
plural ∼ Grails 1 or holy grail [count] : something that you want very much but that is very hard to get or achieve
▪ Finding a cure for cancer is the holy grail of medical researchers. 2 the Holy Grail : the cup that is said to have been used by Jesus Christ and that was sought by knights during the Middle Ages
▪ Finding a cure for cancer is the holy grail of medical researchers.
