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

• repeal
• repealable
• repeat
• repeatable
• repeated
• repeatedly
• repeater
• repeating
• repeating decimal
• repeating firearm
• repel
• repellant
• repellent
• repellently
• repeller
• repelling
• repellingly
• repent
• repentance
• repentant
• repentantly
• repercuss
• repercussion
• repercussive
• repertoire