hypogeum
\ hahy-puh-JEE-uhm, hip-uh- \ , noun;
1.an underground burial chamber.
2.Ancient Architecture . the underground part of a building, as a vault.
Quotes:
All these royal personages are successively named in the inscriptions of the hypogeum , and thus form a supplement, and a valuable confirmation, of the table of Abydos.
-- Sylvanus Urban, "Champollion’s Egyptian Expedition," The Gentleman's Magazine , Vol. 146, 1829
It was then that the prehistoric temples were unearthed, the most impressive of them being the Hypogeum , carved below ground from solid rock.
-- Charles Grech-Orr, "Malta Digs into Its Past," New York Times , February 26, 1961
Origin:
Hypogeum comes from the Greek word hypógeion meaning “underground chamber.” It entered English in the early 1700s.
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