Wiktionary
abo group
alt. (context medical English) The basic system of categorizing blood by antigen type.(R:MW3 1976: page=4) n. (context medical English) The basic system of categorizing blood by antigen type.(R:MW3 1976: page=4)
Wikipedia
Abo Group
The Abo Group is a geologic group in New Mexico. It preserves fossils dating back to the Permian period.