rift rigid rigor rigorous rim rinse riot rip ripe ripen ritual rival rivalry roar roast robbery robe rod roll roller rot rotary rotten rough routine row royal royalty rub rubella ruby rug rupture rural rust rabies racial racism racist rack radial radiate radiation radical radicle radioactive radiograph radiology radiotherapy radius rag rage raid rail rake rale rally ramble ramify rancher rarity rascal rash ratify rating ration rational rationale ravage razor reactionary reactivate reagent realm ream reap rear reassure rebellious rebuke recede receptacle recipe recipient reciprocal recite reck recklessly reckon reclaim recline recoil recollect recombination recommend recommendation reconcile reconciliation recondition reconstruct recreation recrudesce recruit rectify rectitis rectum recumbent recur reel referral refine refluent refractory refrain refresh refreshment refugee refusal refute regimen regression rehabilitate rehearsal reign reinforce relapse relaxant relay relevance relevant reliability reliable relic relief relieve religion religious reluctance reluctant remedy remit remittent remnant removal renal render repeal repel repent repetition replicate represent representative repress repression reproach reproduce repulsion reputation requisite rescue resect resemblance resemble resent reserve reservoir reside residence resident residual residue resign resignation resin resistant resoluble resolute resolution resonance resonate resort respective respiration respire respond response responsibility responsible restore restrain restraint restrict restriction resultant resume retail retard retell retention reticular retina retire retract retreat retrieve retrograde reunification reunion reveal revenge revenue reverse reversible reversion revise revision revitalize revive revolt revolve rheumatism rheumatoid rhinitis rib ribbon rickets riddle ridicule ridiculous rifle