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; see origin at under, croft ¹

Example Sentences

Eight and a half years ago, I attended my first in-person meeting, in the undercroft of a Unitarian Church in Brooklyn.

From New York Times • Apr. 2, 2020

Further along is the oldest part of the abbey, the undercroft, used as the treasury.

From Washington Post • Jan. 10, 2019

I had a CVS employee show me how to use a price scanner, and a church employee tell me what an undercroft is.

From New York Times • Jan. 7, 2018

Taking inspiration from the atmospheric fan-vaulted undercroft of the 1600s Lincoln’s Inn Chapel, Grafton Architects have proposed an internal structure that appears to grow in branching, tree-like umbrellas as it rises through the building.

From The Guardian • Jan. 15, 2017

Thus the fine early Norman undercroft of the prior’s hall is probably of the time of Abbot Simeon.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 3 "Electrostatics" to "Engis" by Various