vault
/vɒlt//vɑlt/noun
Definitions
An arched masonry structure supporting and forming a ceiling, whether freestanding or forming part of a larger building.
Any arched ceiling or roof.
Anything resembling such a downward-facing concave structure, particularly the sky and caves.
The space covered by an arched roof, particularly underground rooms and church crypts.
verb
Definitions
To build as, or cover with a vault.