act of calling upon or summoning a spirit, demon, god or other supernatural agent

The Summoner is one of the characters in the Canterbury Tales. He is always drunk. Children are afraid of him. When he drinks too much wine, he starts speaking in Latin. He has pimples on his face but is rather intelligent. Chaucer used to write about the medieval age. Anachronism can be found in his writings easily. Everything that he has described about the Summoner is set in that time.