undercroft

American  

[uhn-der-krawft, -kroft] / ˈʌn dərˌkrɔft, -ˌkrɒft /

noun

1. a vault or chamber under the ground, especially in a church.

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undercroft British  

/ ˈʌndəˌkrɒft /

noun

1. an underground chamber, such as a church crypt, often with a vaulted ceiling

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Etymology

Origin of undercroft

Middle English word dating back to 1350–1400; under, croft ¹

Example Sentences

Part of the undercroft roof will be removed so equipment can be lowered into the workspace by crane.

From Washington Post

Floor-to-ceiling glass walls will provide a view of some of the supports in the undercroft, and an immersive theater presentation will project images of historic events onto the foundations, the Park Service said.

From Washington Post

The undercroft includes the huge grid of exposed concrete columns and arched supports that hold up the memorial.

From Washington Post

Much of the work will be done in the basement “undercroft” of the massive structure, where extensive new exhibit areas will be created.

From Washington Post

It’s delightful to learn that the Undercroft, a basement lair under Doctor Strange’s Sanctum where deep magic is concocted, also doubles as the wizard’s laundry room.

From Seattle Times