| A | B |
| Quip | to make a quick, witty response |
| Quixotic | having the same romantic idealism as Don Quixote |
| Quorum | the minimum number of people who have to be at a meeting in order to make decisions |
| Rampage | a course of wild or violent behavior |
| Rampant | unrestrained |
| Rant | to rave or speak wildly |
| Rapacious | plundering; greedy |
| Rapprochement | reconciliation; re-establishment of good relations |
| Ratiocination | logical, methodical thinking |
| Rationalize | to make rational; to justify |
| Ravage | to bring destruction; to plunder or pillage |
| Ravenous | very hungry |
| Raze | to tear down; to demolish |
| Realm | kingdom |
| Recalcitrant | stubborn; unbending |
| Recapitulate | to repeat, often in a briefer manner |
| Reciprocal | mutual; working both ways |
| Recondite | hard to understand; profound; abstruse |
| Rectify | to correct or set right |
| Recumbent | lying down |
| Redolent | fragrant |
| Redoubtable | frightening |
| Redress | to correct an injustice |
| Redundant | repetitious; to necessary |
| Refractory | disobedient |
| Refulgent | shining; radiant |