13 letters
- microscopists25
- misanthropies22
- misdeveloping28
- monophthongal28
- monopsonistic24
- mycetophagous29
- myrmecophiles30
- mythopoetical27
- nannoplankton26
- nasopharynges24
- nasopharynxes29
- naturopathies20
- necrophiliacs26
- necrophilisms26
- neoplasticism24
- neoplasticist21
- nephropathies24
- neuropeptides22
- nincompoopery29
- nitroparaffin24
- noncooperator21
- nucleoplasmic29
- nucleoprotein23
- oligopolistic23
- onomatopoeias20
- onomatopoetic23
- onychophorans27
- openabilities21
- openheartedly23
- openmouthedly27
- operabilities20
- operationally21
- operationisms20
- operationists17
- operativeness21
- operosenesses17
- ophthalmology29
- opinionatedly22
- opisthobranch27
- opportuneness22
- opportunistic24
- opportunities21
- oppositionist20
- opprobriously26
- optimisations20
- optimizations29
- optionalities18
- oropharyngeal24
- orthopterists18
- orthopteroids19
- oscilloscopes24
- oscilloscopic27
- osteoplasties17
- outpopulating25
- overdeveloped27
- overoperating23
- overoptimisms26
- overoptimists23
- overpopulated26
- overpopulates25
- pancytopenias26
- panleukopenia27
- phanerophytes26
- pharmacopeial28
- pharmacopeias27
- pharmacopoeia27
- philanthropic28
- philosophical28
- philosophised25
- philosophises24
- philosophized34
- philosophizer33
- philosophizes33
- photoperiodic25
- photopolymers27
- photopositive25
- photoproducts26
- phototropisms24
- phragmoplasts27
- phreatophytes25
- phreatophytic28
- phytopathogen28
- phytoplankter29
- phytoplankton30
- pneumatophore26
- pogonophorans25
- polypropylene29
- porphyropsins27
- postoperative23
- precopulatory26
- premenopausal25
- propaedeutics24
- propagandists23
- propagandized33
- propagandizer32
- propagandizes32
- prophetically28
- prophylactics30
- propinquities30
- propitiations20
- proportionals21
- proportionate20
- proportioning23
- propositional21
- propositioned21
- propoxyphenes34
- proprietaries19
- proprietorial20
- proprioceptor25
- prosopography28
- prosopopoeias22
- prototrophies21
- psychopathics31
- psychopathies28
- psychophysics33
- psychotropics29
- psychrophilic32
- pteridophytes24
- pyrophosphate28
- pyrophyllites27
- radioisotopes17
- radioisotopic20
- reappropriate22
- redevelopment26
- repopularized31
- repopularizes30
- repopulations22
- retinopathies19
- retinoscopies20
- rhinoplasties20
- sarcophaguses24
- schizophrenes33
- schizophrenia33
- schizophrenic36
- scleroprotein21
- sharecroppers24
- sharecropping27
- sigmoidoscopy27
- siphonophores24
- somatopleures21
- somatotrophin22
- somatotropins20
- sophistically25
- sophisticated22
- sophisticates21
- spectroscopes25
- spectroscopic28
- spermatophore24
- spermatophyte26
- sporopollenin23
- stereophonies19
- stereopticons20
- stereoscopies19
- strophanthins22
- suboptimizing35
- subpopulation26
- sycophantisms27
- synchroscopes27
- tachistoscope24
- technophobias27
- theophyllines25
- thermophilous25
- thermoplastic25
- thermotropism24
- thigmotropism26
- thyrotrophins23
- toplessnesses18
- topographical27
- topologically26
- toxoplasmoses27
- toxoplasmosis27
- tracheophytes25
- triceratopses19
- trichopterans22
- trimethoprims24
- trophoblastic25
- tropicalizing32
- tropocollagen24
- uncooperative25
- urethroscopes22
- xerophthalmia31
- xerophthalmic34
- zooplanktonic35