bestiary
Concise Oxford English Dictionary © 2008 Oxford University Press:
bestiary /ˈbɛstɪəri/
▶noun (pl. bestiaries) a treatise on animals, especially a medieval work with a moralizing tone.
– origin C19: from med. L. bestiarium, from L. bestia ‘beast’.
'bestiary' also found in these Oxford entries:

