- ritenuto
- ram dump
- ram refresh
- ram loader
- ramp
- roughness
- ragpicker's disease
- ragsorter's disease
- raman shift
- ramapithecus brevirostis
- ramapithecus
- ramisectomy
- robustious
- raymond lully
- ramify
- ramon flocculation test
- rammstedts operation
- reviewing stand
- rattler
- ramsay_hunts syndrome
- ramus lingualis vagi
- ranch
- rancid
- random distribution of gene
- random access device
- random number sequence
- random test
- random scan
- random variation
- righteous action
- randomized block design
- ruttish
- rangoon creeper
- ranger
- ranking
- rutherford b. hayes
- ruth st. denis
- remorselessly
- russia
- rubella
- ruben non_rebreathing value
- rubinstein
- rubrothalamic tract
- ruble
- red raspberry
- ruby
- rubicelle
- ruhr
- run out
- run phase