is the chest containing relics, or the shrine thereof (Latin, capella; French, chape, a cope). The kings of France in war carried St. Martin's cope into the field, and kept it in a tent as a talisman. The place in which the cope was kept was called the chapelle, and the keeper thereof the chapelain.
in printers' parlance, meant his workshop. In the early days of printing, presses were set up in the chapels attached to abbeys, as those of Caxton in Westminster Abbey. (See Monk, Friar , etc.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894