sacellum

[ suh-kel-uh m, -sel- ]
/ səˈkɛl əm, -ˈsɛl- /

noun, plural sa·cel·la [suh-kel-uh, -sel-uh] /səˈkɛl ə, -ˈsɛl ə/.

a small chapel, as a monument within a church.
(in ancient Rome) a shrine open to the sky.

Origin of sacellum

1800–10; < Latin: shrine, derivative of sacer holy, sacred; for formation see castellum
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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