monstrance vs pyxis

monstrance

noun
  • An ornamental, often precious receptacle, either open or with a transparent cover, in which the sacramental bread (consecrated host) is placed for Eucharistic adoration. 

pyxis

noun
  • A small box 

  • A nautical compass 

  • A capsule in which the lid separates from the top of the fruit to release the seeds; a pyxidium 

  • The box in which ashes are stored for Ash Wednesday 

  • acetabulum 

How often have the words monstrance and pyxis occurred in a corpus of books? (source: Google Ngram Viewer )