Original: Red blood cells are also known as RBCs , red blood corpuscles ( an archaic term ) , haematids , erythroid cells or erythrocytes ( from Greek erythros for '' red '' and kytos for '' hollow '' , with cyte translated as '' cell '' in modern usage ) .
Simplified: Red blood cells ( also known as RBCs , red blood corpuscles or erythrocytes ) are cells that make up blood .