- red dwarf star
- rna ladder
- reddish_striped
- rotary tillage
- republic of botswana
- riemannian
- republic of sierra leone
- random access sort
- random key_to address transformation
- roth
- reactive depression
- richter hernia
- rhizopoda
- rhodopsin
- read back check
- rhomboideus
- reflex dystrophy
- reflex hallucination
- robert andrews millikan
- record layout
- record name
- rio de janeiro
- rectal catheter
- rectal thiopentone
- rotational viscosimeter
- radicular odontoma
- river cocytus
- red as a beetroot
- red scare
- resistant strain
- right atrium
- relational data base
- rights offering
- real ira
- reconciling
- rhombohedral
- radio opaque stone
- resistant line
- resistant mutant
- resistant pyoderma
- resistant spore
- river severn
- revolving charge account
- reproductive cell
- reginald carey harrison
- right atrioventricular valve
- rollmops
- rendered still
- recto uterine pouch
- reinhold niebuhr