15 letters
- pharisaicalness25
- pharmaceuticals31
- pharmacodynamic36
- pharmacognostic32
- pharmacokinetic34
- pharmacological33
- phenomenalistic29
- phenylketonuric33
- philanthropical31
- philosophically33
- phonogramically33
- photobiological30
- photochemically35
- photoduplicated30
- photoduplicates29
- photoelectronic28
- photogeological29
- photogrammetric31
- photomechanical33
- photometrically30
- photomicrograph33
- phototactically30
- phototoxicities30
- phototropically30
- physicochemical37
- physiographical33
- physiologically32
- phytochemically37
- phytogeographic34
- phytopathogenic33
- phytoplanktonic35
- phytotoxicities32
- pictorialnesses23
- picturesqueness33
- pinocytotically31
- planimetrically30
- plasticizations32
- platyhelminthic33
- pluralistically28
- plutocratically30
- politicizations32
- polymorphically36
- postapocalyptic33
- posthemorrhagic30
- practicableness29
- practicalnesses26
- preagricultural27
- prefabrications28
- prehistorically27
- prejudicialness34
- premodification29
- prenotification26
- prepublications30
- presynaptically31
- prettifications25
- problematically32
- prognosticating27
- prognostication25
- prognosticative28
- prognosticators24
- progressivistic27
- proteolytically28
- psychedelically34
- psychiatrically32
- psychoacoustics32
- psychochemicals37
- psychogenically35
- psychologically35
- psychometrician32
- psychoneurotics30
- psychophysicist35
- psychotomimetic34
- pyroelectricity29
- pyrotechnically33
- quadruplicating37
- quadruplication35
- quadruplicities34
- quantifications33
- quintuplicating37
- radicalizations30
- radiobiological26
- radiochemically31
- radiometrically26
- radiotelemetric23
- recertification25
- recodifications26
- reduplicatively31
- refortification25
- replicabilities26
- republicanizing39
- requalification33
- restrictionisms22
- restrictionists19
- restrictiveness23
- revivifications30
- rigidifications25
- ritualistically24
- romanticization32
- sabermetricians25
- sadomasochistic27
- sanctifications26
- saponifications26
- saprogenicities24
- saprophytically32
- semicentennials25
- semicolonialism27
- semicrystalline26
- semicylindrical30
- semilogarithmic29
- serviceableness27
- sesquicarbonate32
- sesquicentenary32
- silicifications26
- silviculturally30
- silviculturists26
- simplifications29
- socialistically26
- sociobiological28
- sociohistorical24
- sociolinguistic26
- solidifications24
- solipsistically26
- sophisticatedly27
- sophistications24
- stereologically25
- stereotaxically29
- stereotypically27
- stoichiometries23
- stratifications22
- streptothricins24
- stultifications24
- submetacentrics29
- superefficiency34
- superplasticity28
- sycophantically33
- syllabification29
- syllogistically28
- symmetricalness28
- sympathetically32
- sympathomimetic34
- symptomatically33
- symptomatologic32
- synchronicities27
- synecdochically34
- synergistically27
- technologically31
- telegraphically30
- telekinetically28
- theatricalities21
- theatricalizing33
- therapeutically28
- thermodynamical31
- thunderstricken28
- topographically32
- toxicologically35
- transhistorical22
- trichomonacidal29
- trichomonacides28
- trigonometrical25
- typographically34
- ultrademocratic27
- ultramicroscope29
- ultramicrotomes26
- unanticipatedly28
- unchronological30
- uncommunicative35
- underpublicized39
- unrealistically25
- unsophisticated26
- unsymmetrically32
- vasoconstrictor26
- ventriloquistic34
- vicariousnesses24
- vicissitudinous26
- viscoelasticity28
- voicelessnesses24
- voyeuristically29
- whimsicalnesses28
- xerographically36
- zoogeographical37