baptistērĭum

ii, n.
I. A place for bathing or swimming, a vessel for bathing, Plin. Ep. 5, 6, 25; 2, 17, 11; Sid. Ep. 2, 2.—
II. In eccl. Lat., a baptistery, a baptismal font, Sid. Ep. 4, 15.
Lewis & Short
A Latin Dictionary, 1879
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