14 letters
- preponderating25
- preponderation23
- prepossessions21
- preposterously24
- presupposition25
- proportionable25
- proportionably27
- proportionally25
- proportionated22
- proportionates21
- propositioning24
- protoporphyrin28
- purposefulness27
- reappointments25
- reapportioning24
- recompositions24
- redispositions19
- reexportations25
- reimportations21
- reincorporated22
- reincorporates21
- repolarization28
- repopularizing34
- responsibility24
- responsiveness23
- saponification25
- semiporcelains25
- seropositivity23
- sociopolitical25
- spatiotemporal24
- spokesmanships30
- sporangiophore25
- sporopollenins24
- sporotrichoses22
- sporotrichosis22
- sportfisherman26
- sportfishermen26
- sportfulnesses23
- sportivenesses22
- sportscastings23
- sportsmanships26
- sportswritings23
- spotlessnesses19
- subpopulations27
- superimposable28
- superpositions22
- supportability27
- supportiveness26
- supposititious22
- tablespoonfuls27
- tablespoonsful27
- teleportations19
- temporizations30
- transportation19
- transpositions19
- treponematoses21
- treponematosis21
- tropocollagens25
- tropologically27
- uncontemporary28
- underexposures28
- underpopulated26
- underreporting23
- unincorporated24
- unpopularities24
- unresponsively27
- urediniospores20
- vaporishnesses24
- vaporousnesses23