1. A classification system for the antigens of human blood; used in blood transfusion therapy; four groups are A and B and AB and O
   - ABO blood group system, ABO system

Type of: classification system

• Gymnorhina
• Gymnorhina tibicen
• gymnosophical
• gymnosophist
• gymnosophy
• gymnosperm
• gymnosperm family
• gymnosperm genus
• Gymnospermae
• Gymnospermophyta
• gymnospermous
• gymnospermous tree
• gymnospermous yellowwood
• Gymnosporangium
• Gymnosporangium juniperi-virginianae
• Gymnura
• gymslip
• gynaec-
• gynaeco-
• gynaecocracy
• gynaecologic
• gynaecological
• gynaecologist
• gynaecology
• gynaecomastia