Definition of baptistry in English English dictionary
A designated space within a church, or a separate room or building associated with a church, where a baptismal font is located, and consequently, where the sacrament of Christian baptism (via aspersion or affusion) is performed
or baptistry Domed hall or chapel, adjacent to or part of a church, for the administration of baptism. By the 4th century, the baptistery had assumed an eight-sided shape (eight in Christian numerology being the symbol for a new life), as had the baptismal font within. The font itself was set beneath a dome-shaped baldachin and encircled by columns and an ambulatory (aisle), features first used by the Byzantines