15 letter words
RADIOGONIOMETER​19
RADIOMICROMETER​22
14 letter words (7 words)
REMANUFACTURER​21
RADIOTELEMETER​17
RETROREFLECTOR​19
REVOLUTIONISER​17
REVOLUTIONIZER​26
RHOMBENPORPHYR​31
RHYPAROGRAPHER​28
13 letter words (10 words)
ROLLERCOASTER​15
REFRACTOMETER​20
REFLECTOMETER​20
REHABILITATOR​18
RECONSTRUCTOR​17
RESTAURANTEUR​13
REALPOLITIKER​19
RECONNOITERER​15
REINVIGORATOR​17
RIVERWORTHIER​22
12 letter words (31 words)
REFRIGERATOR​16
RESTAURATEUR​12
RADIOGRAPHER​19
RENOVASCULAR​17
RESUSCITATOR​14
RATIOCINATOR​14
RATIONALISER​12
RATIONALIZER​21
READMINISTER​15
RECEPTACULAR​18
RECIPROCATOR​18
RECONNOITRER​14
RECRIMINATOR​16
REDEMPTIONER​17
REDISCOVERER​18
RELINQUISHER​24
REMEMBRANCER​20
REMONSTRATOR​14
REPROGRAPHER​20
RESOLUTIONER​12
11 letter words (41 words)
RECTANGULAR​14
RANGEFINDER​16
RECOMMENDER​18
REGENERATOR​12
RECTILINEAR​13
REPLENISHER​16
REJUVENATOR​21
REDEVELOPER​17
RADIOTRACER​14
RECONNOITER​13
RETROBULBAR​15
RATHSKELLER​18
REPOSSESSOR​13
RACETRACKER​19
RAKEHELLIER​18
REAPPRAISER​15
RECOMPENSER​17
RECUPERATOR​15
REDECORATOR​14
REDELIVERER​15
10 letter words (88 words)
RESEARCHER​15
RECONSIDER​13
ROTTWEILER​13
RAPPORTEUR​14
RESPIRATOR​12
ROADRUNNER​11
REPLICATOR​14
REDISCOVER​16
RADIOMETER​13
RANDOMIZER​22
RINGMASTER​13
RECOGNIZER​22
RAILROADER​11
RINGLEADER​12
ROCKHOPPER​23
REINFORCER​15
REFERENCER​15
REENGINEER​11
REREGISTER​11
REFINISHER​16
9 letter words (112 words)
REGISTRAR​10
REMAINDER​12
RESERVOIR​12
REGULATOR​10
RECRUITER​11
RETRIEVER​12
REFLECTOR​14
RESPONDER​12
REFRESHER​15
REQUESTER​18
RAINWATER​12
RECTIFIER​14
RESONATOR​9
REPRESSOR​11
REQUESTOR​18
REFRACTOR​14
RITONAVIR​12
RAINMAKER​15
RECHARGER​15
REMODELER​12
8 letter words (174 words)
REGISTER​9
REMEMBER​14
RECEIVER​13
REPORTER​10
RECORDER​11
REVIEWER​14
RETAILER​8
RECEPTOR​12
RESELLER​8
REMINDER​11
RADIATOR​9
ROLLOVER​11
RESISTOR​8
REFERRER​11
REVOLVER​14
REPEATER​10
ROADSTER​9
REINDEER​9
RETAINER​8
RECLINER​10
7 letter words (146 words)
REGULAR​8
RECOVER​12
REALTOR​7
REACTOR​9
REMOVER​12
RICHTER​12
ROOSTER​7
RAMBLER​11
RAINIER​7
ROUNDER​8
REORDER​8
ROTATOR​7
RANCHER​12
REDUCER​10
ROASTER​7
REVISOR​10
REENTER​7
REFINER​10
RESCUER​9
ROUGHER​11
6 letter words (114 words)
RATHER​9
READER​7
REPAIR​8
ROUTER​6
RUBBER​10
ROLLER​6
ROSTER​6
RUNNER​6
RENDER​7
RANGER​7
RIPPER​10
RINGER​7
RAIDER​7
ROCKER​12
RICHER​11
REAPER​8
RENTER​6
RAPTOR​8
RASTER​6
RECTOR​8
5 letter words (35 words)
RIVER​8
REFER​8
ROGER​6
RADAR​6
RIDER​6
ROVER​8
RACER​7
RAZOR​14
RULER​5
RUMOR​7
ROTOR​5
RISER​5
ROPER​7
RIGOR​6
RECUR​7
RAZER​14
RATER​5
RARER​5
REBAR​7
RAVER​8
4 letter words
REAR​4
ROAR​4
RUER​4