sanctum sanctorum
Concise Oxford English Dictionary © 2008 Oxford University Press:
sanctum sanctorum /saŋ(k)ˈtɔːrəm/
▶noun (pl. sancta sanctorum or sanctum sanctorums) the holy of holies in the Jewish temple.
– origin ME: L. sanctum (see sanctum) + sanctorum ‘of holy places’, translating Heb. qōḏeš haqqŏḏāšīm ‘holy of holies’.
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