Wiktionary
onolatry
n. 1 worship of the ass or donkey. 2 preoccupation with or devotion to something foolish.
Wikipedia
Onolatry
Onolatry is worship of the donkey. In Imperial Rome, the charge of onolatry was used by the pagans to taunt the Jews and first Christians. A famous example of this is the Alexamenos graffito.