the.com/sacred cow

An idea too worshipped to question, even as it quietly ruins everything it touches.

means A belief, tradition, or institution treated as immune from criticism or change, regardless of whether it still makes sense.

from Drawn directly from the Hindu reverence for cows, which are protected from slaughter and harm in Indian culture — a practice Western observers, often clumsily, singled out as a symbol of untouchable belief. By the early 20th century, English speakers had lifted the image out of its religious context and turned it into a secular jab: any policy, person, or pet idea so sanctified by habit or power that pointing out its flaws feels like blasphemy.

origin
Literally Hindu cattle, protected from slaughter
modern use
Coined by Western journalists mocking untouchable policies
irony
The phrase itself is now a sacred cow
best use
Precedes the words that must be slaughtered
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