catacomb
/ˈkatəkuːm/
noun(often plural) An underground system of tunnels and chambers with recesses for graves, used (in former times) as a cemetery; a tunnel system used for burying the dead, as in Paris or Ancient Rome.
(often plural) An underground system of tunnels and chambers with recesses for graves, used (in former times) as a cemetery; a tunnel system used for burying the dead, as in Paris or Ancient Rome.