From The Collaborative International Dictionary of English v.0.48 [gcide]:
Catacomb \Cat"a*comb\, noun [It. catacomba, fr. L. catacumba perh. from Gr. kata' downward, down + ky'mbh cavity.] A cave, grotto, or subterraneous place of large extent used for the burial of the dead; -- commonly in the plural.
Note: The terms is supposed to have been applied originally to the tombs under the church of St. Sebastian in Rome. The most celebrated catacombs are those near Rome, on the Appian Way, supposed to have been the place or refuge and interment of the early Christians; those of Egypt, extending for a wide distance in the vicinity of Cairo; and those of Paris, in abandoned stone quarries, excavated under a large portion of the city.
From WordNet (r) 3.0 (2006) [wn]:
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