It was probably first built as a basilica and as the catholicon of a monastery.
From the en.wikipedia.org
In 1845 he expanded the catholicon of the monastery, adding two chapels, a vestibule and a porch to it.
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In the centre of this court stands the catholicon or conventual church, a square building with an apse of the cruciform domical Byzantine type, approached by a domed narthex.
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Panacea: hypothetical remedy for all ills or diseases; once sought by the alchemists
In pre-modern medicine, catholicon was a soft electuary, so called as being supposedly universal in its curative and prophylactic abilities (see panacea); or a purger of all humours.
The Summa grammaticalis quae vocatur Catholicon, or Catholicon, was completed March 7, 1286 by John Balbi (Johannes Januensis de Balbis), of Genoa, a Dominican. The Catholicon was a religious Latin dictionary which found wide use throughout Christendom.