1. A low level of prothrombin (factor II) in the circulating blood; results in long clotting time and poor clot formation and sometimes excessive bleeding; can result from vitamin K deficiency

Type of: blood disease, blood disorder

• riveting
• riveting machine
• rivetter
• Riviera
• Rivina
• Rivina humilis
• rivulet
• rivulus
• Riyadh
• riyal
• riyal-omani
• rms
• Rn
• RNA
• RNA polymerase
• RNase
• RNIB
• RNLI
• Ro
• ro-ro
• roach
• roach clip
• roach holder
• roaching
• road