say it: KAT-uh-kohm
catacomb is a noun meaning "an underground tunnel with recesses where bodies were buried (as in ancient Rome)". It carries one recorded sense.
an underground tunnel with recesses where bodies were buried (as in ancient Rome)
Rome · antiquity
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for catacomb come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.