catacomb
Catacomb (noun) means an underground network of tunnels and rooms with spaces for graves, once used as a burial place, such as those beneath Paris or ancient Rome.
Etymology
From Middle English catacombe, from Old English catacumbe, catacumbas pl, from Late Latin catacumbae pl, name of the underground cemetery of St. Sebastian in Rome, of unclear origin. Perhaps a dissimilation (influenced by *cumbō (“to lie, recline”)) of Late Latin cata tumbās (literally “among the tombs”) (from Ancient Greek κατά (katá, “under”) and τύμβος (túmbos, “tomb”)). Some sources suggest Ancient Greek κύμβη (kúmbē, “drinking vessel”) as an alternative etymon, but the semantic link is unclear.