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"In architecture the slab or plinth which forms the upper member of the capital of a column or pillar, and upon which rests, in classic styles, the lower surface of the achitrave."—Wright, 1902

Abacus

"In architecture the slab or plinth which forms the upper member of the capital of a column or pillar,…

"Fenestella. In Roman Catholic churches, a niche on the south side of an altar, containing the piscina, and frequently also the credence." -Whitney, 1911

Fenestella in the Church of Norrey

"Fenestella. In Roman Catholic churches, a niche on the south side of an altar, containing the piscina,…