holy_of_holies has definitions from the fields of Judaism,religion,geography
1
[ noun ] (religion) something that is regarded as inviolable or sacred

Examples

"every politician fears to touch that holy of holies, the Social Security System"

Related terms

entity sacredness

2
[ noun ] (Judaism) sanctuary comprised of the innermost chamber of the Tabernacle in the Temple of Jerusalem where the Ark of the Covenant was kept
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