DIC abdicate abdication dedicate dedication indicate indication index predicate prediction diction dictionary dictate dictation dictator dictum benediction condition contradict contradiction contradictious indict interdict predict sedition valedictory verdict vindicate edict interdiction jurisdiction malediction

　　GNI/GNO agnostic cognition cognizable cognizance cognizant diagnose ignore ignorance ignorant prognosticate recognize recognizable recognition cognitive diagnosis incognito prognosis

　　APT/EPT apt aptness adapt adaptable adaptive inapt inaptitude adaptation aptitude adept inept

　　ART artist artistic artless artificial artful artifact artifice artisan

　　CAD/CID/CAS cadence decadence accident accidental deciduous incidence incident incidental coincide coincidence coincident Occident cascade case casual occasion occasional cadaver casualty decadent recidivism

　　CIS concision decide decision decisive excision fratricide incise incision insecticide matricide patricide precise suicide concise excise incisive precision

　　RAD/RAS abrade abrasion abrasive erase erasable eraser erasure raze razor

　　RADI radical radicalism radicalize radicalization radicand radish radix eradicate eradicable eradication eradicator

　　RADI radium radius radial radiate radiation radiator radiant radio radioactive radioactivity radiology radiotelephone radiotherapy irradiate irradiation irradiant irradiance

　　RAP/RAV rape rapist rapacious rapacity rapid rapidity rapt rapture enrapt enrapture rapturous raptorial ravage raven ravening ravish ravishment

　　RAT/RATIO ratify ratio ratiocinate ratiocination ration rational rationale rationalism rationalist rationality rationalize rationalization irrational irrationality

　　REG regal regalia regality regent regency regicide regime regiment Regina regius region realm regnant reign regular regularity regulate regulation irregular royal royalty rigid rigidity rigor rigorous

　　REPT reptile reptilian surreptitious

　　RID/RIS ridicule ridiculous risible risibility deride derision derisive derisory

　　ROD/ROS rodent corrode corrosion corrosive erode erosion erosive

　　ROT rotary rotate rotation rotational rotator rotor rotund rotunda rotundity dextrorotatory levorotatory

　　RUD rude rudiment rudimental rudimentary erudite erudition

　　RUPT rupture abrupt abruption bankrupt bankruptcy corrupt corruption disrupt disruption erupt eruption incorrupt incorruptible interrupt interruption irrupt irruption route routine

　　RUR/RUS rural rustic rusticate rustication rusticity