1. The blood group whose red cells lack the Rh factor (Rh antigen)
   - Rh-negative blood type, Rh negative

Type of: blood group, blood type

• family Rhizopogonaceae
• family Rhodymeniaceae
• family Rhyniaceae
• family Rickettsiaceae
• family Roccellaceae
• family room
• family Roridulaceae
• family Rosaceae
• family Rubiaceae
• family Ruscaceae
• family Russulaceae
• family Rutaceae
• family Rynchopidae
• family Saccharomycetaceae
• family Sagittariidae
• family Salamandridae
• family Salicaceae
• family Salmonidae
• family Salpidae
• family Salvadoraceae
• family Salviniaceae
• family Santalaceae
• family Sapindaceae
• family Sapotaceae
• family Sarcoptidae