"A sacred cow since the late '80s, now it's run its course," Reed said.
Additionally, there is no upside in our media culture to challenging this sacred cow.
“She took the sacred cow and made a hybrid woman cow which is called Holy Daughter,” Adicéam said.
Figuratively, anything that is beyond criticism: “That housing project is a real sacred cow: the city council won't hear of abandoning it.” In India, followers of Hinduism consider cows sacred and do not eat them because they believe the animals contain the souls of dead persons.
Someone or something that may not be questioned or altered: Everything is on the table. There are no sacred cows
[1910+; fr the venerated status of cows in Hinduism]