14 letters
- proportionably27
- proportionally25
- proportionated22
- proportionates21
- propositioning24
- proprioception27
- proprioceptive30
- proprioceptors26
- protectionisms24
- protectionists21
- pseudoscorpion26
- psychobiologic33
- pugnaciousness26
- pulverizations33
- pyrheliometers25
- pyrheliometric28
- quadrillionths30
- qualifications32
- quantification32
- questionnaires26
- quindecillions32
- quintillionths30
- radicalization29
- radioautograph23
- radiobiologies21
- radiobiologist21
- radiochemistry25
- radioecologies21
- radiolabelling24
- radiologically25
- radiolucencies24
- radiosensitive20
- radiostrontium20
- radiotelegraph23
- radiotelemetry21
- radiotelephone22
- radiotelephony24
- radiotherapies20
- radiotherapist20
- rambunctiously29
- randomizations29
- ratiocinations19
- rationalizable29
- rationalnesses17
- reacquisitions28
- reactionaryism23
- reaffirmations24
- reaggregations21
- reapplications25
- reapportioning24
- reattributions19
- rebelliousness21
- recalculations24
- recalibrations22
- recanalization29
- recapitulation23
- reciprocations24
- recirculations23
- recodification25
- recolonization29
- recombinations25
- recommendation26
- recommissioned25
- recompilations25
- recompositions24
- recomputations25
- reconciliation23
- reconditioning23
- reconfirmation25
- reconsecration22
- reconstitution20
- reconstruction23
- recreationists18
- recriminations22
- rectifications24
- redescriptions22
- redintegration19
- redispositions19
- redistillation18
- redistribution20
- reductionistic23
- reduplications24
- reexaminations26
- reexportations25
- reforestations18
- reformulations23
- refrigerations20
- regimentations21
- regularization28
- regurgitations20
- rehabilitation21
- reimplantation23
- reimportations21
- reincarnations20
- reinfestations19
- reinnervations21
- reinoculations21
- reinstallation18
- reintegrations18
- reintroduction21
- reinvigoration22
- relubrications23
- remobilization31
- remonetization28
- remonstrations19
- renationalized27
- renationalizes26
- renegotiations18
- reorganization27
- reorientations16
- repartitioning21
- repolarization28
- representation19
- repristination19
- reprovisioning25
- republications26
- repudiationist20
- repunctuations24
- requisitioning28
- reregistration17
- resegregations19
- reservationist19
- restimulations20
- restrictionism21
- restrictionist18
- resurrectional20
- resuscitations19
- retranslations17
- retransmission19
- retroflections22
- retrogradation18
- retrogressions17
- retrospections21
- reunifications23
- reutilizations26
- revaccinations26
- revalorization29
- reverberations22
- revitalization29
- revivification29
- revolutionised22
- revolutionises21
- revolutionists21
- revolutionized31
- revolutionizer30
- revolutionizes30
- rhythmizations33
- rigidification24
- ritualizations26
- robustiousness20
- routinizations26
- ruggedizations30
- sacrilegiously24
- salubriousness21
- sanctification25
- saponification25
- scarifications24
- schematization32
- scintillations21
- sclerotization28
- secularization29
- securitization28
- sedimentations20
- segregationist19
- semasiological24
- semifunctional27
- semiofficially30
- semiologically27
- sensationalise17
- sensationalism20
- sensationalist17
- sensationalize26
- sensitisations16
- sensitizations25
- sensualization27
- separationists18
- sequestrations25
- serializations25
- seriocomically27
- seroconversion23
- sexploitations26
- sexualizations33
- signalizations28
- significations24
- silicification25
- simplification28
- socializations28
- sociobiologies23
- sociobiologist23
- sociolinguists22
- sociologically27
- sociopolitical25
- socioreligious21
- solemnizations29
- solidification23
- solubilization30
- somnambulation27
- sophistication23
- soteriological21
- sovietizations28