Abo

Abo is the abbot of the Benedictine abbey who asks William to investigate the murders of several monks. Abo is more interested in the good name of the abbey than he is in the truth. At the end of the novel, Abo has died, the victim of murder himself.

Adelmo of Otranto

Adelmo is a young illustrator of manuscripts. Before the book opens, he has engaged in a homosexual affair with Berengar, perhaps in order to gain access to an important, yet sequestered, book. As a result, he has committed suicide just before William and Adso's arrival at the abbey.

Adso of Melk

Adso of Melk is an elderly Benedictine monk who writes of his experiences as a young novitiate who accompanies William of Baskervilles on his trip to a northern Italian abbey in 1327 where they encounter a series of murders. Adso thus plays two roles in the...