〔单loculus〕小腔- Ristella melaninogenica
- ristocetin
- risus
- Ritalin
- Ritgen maneuver (method)
- ritodrine
- Ritter-Rollet phenomenon(sign)
- Ritter's disease
- Ritter-Valli law
- ritual
- rivalry
- Rivalta's reaction (test)
- Riva-Rocci sphygmomanometer
- Riviere's sign
- Rivinus's ducts(canals),gland,incisure(for-amen, notch, segment)
- rivus
- riziform
- RKY
- R. L. L.
- R. M. A.
- R. M. L.
- R. M. P.
- R. M. T.
- Rn
- R. N.