Side altar

In Christianity, a side-altar or bye-altar is an altar that is subordinate to the central or high altar in a church. The term is generally applied to altars situated in bays of the nave, transepts, etc.^[1] Side-altars may be recessed in a side-chapel, or simply built against a main aisle wall.

A bye-altar in the Kapucijnenkerk; Ostend, Belgium. Notice the high altar in the background.

In the Catholic Church, before the liturgical reforms arising from the Second Vatican Council, separate Masses were celebrated simultaneously by other priests at bye-altars, even as there is an ongoing Mass at the high altar. After the Second Vatican Council, this practice disappeared subsequent to the introduction of concelebration at the high altar.

Certain churches in the Lutheran tradition of Christianity retained bye-altars, though their presence is not as common today.^[2]

Gallery

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  Bye-altars present to the left and right side of the chancel at Saint Thomas Hospital in Akron, Ohio
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  Bye-altars present to the left and right side of the chancel at St. Stephen Church in Hamilton, Ohio