- nonequilibrium34
- nonpetroleum22
- nostrum12
- notum10
- oakum13
- oceanarium18
- odeum10
- odium10
- odontoglossum22
- oestrum11
- oidium11
- oleum10
- olibanum17
- omasum13
- omentum15
- ommatidium21
- oncidium17
- onium10
- oogonium15
- operculum21
- opium12
- opossum14
- opprobrium23
- optimum17
- opusculum22
- organum14
- origanum15
- osculum16
- osmeterium17
- osmiridium18
- osmium13
- ostensorium16
- ostium10
- outswum15
- ovum12
- pablum17
- pabulum19
- palladium19
- pallium16
- pancratium21
- pandemonium24
- panicum18
- panjandrum29
- pantoum15
- paramecium23
- paramylum22
- parapodium21
- patagium17
- peculium20
- pelargonium22
- pendulum19
- penicillium24
- peplum17
- peponium19
- pericardium22
- perichondrium27
- pericranium22
- peridium16
- perimysium22
- perineum16
- perineurium20
- perionychium27
- periosteum17
- perithecium23
- peritoneum18
- petrolatum18
- petroleum17
- philtrum18
- phosphonium26
- phyllodium24
- phylum18
- pileum14
- pinetum15
- pittosporum21
- planetarium20
- plasmodium22
- plastrum16
- platinum17
- plectrum19
- plenum15
- plum12
- plumbum22
- plutonium19
- podium14
- podophyllum28
- polemonium22
- pollinium19
- polonium17
- polygonum22
- pomatum17
- positronium19
- possum13
- postbellum22
- postpartum20
- potassium16
- practicum22
- praesidium18
- praseodymium25
- premium17
- presidium17
- primordium21
- principium24
- procambium26
- proctodaeum22
- promethium22
- pronotum16
- propylaeum23
- proscenium21
- prostomium20
- protactinium23
- prothalamium25
- prothallium22
- protium14
- psalterium18
- pseudopodium25
- psyllium19
- pterygium20
- pudendum19
- puerperium21
- puparium19
- pycnidium23
- pygidium20
- pyrethrum20
- pyxidium25
- quadrennium28
- quadrivium29
- quantum22
- quinquennium39
- quorum20
- radiostrontium20
- radiothorium19
- radium11
- ramentum16
- rectum13
- referendum19
- refugium18
- regnum13
- reptilium17
- residuum14
- responsum17
- reticulum18
- retinaculum21
- rhenium14
- rheum11
- rhizobium27
- rhodium14
- rosarium12
- rostellum15
- rostrum11
- rubidium17
- rum7
- ruthenium17
- rutherfordium24
- sacrarium16
- sacrum13
- sagum11
- samarium15
- sanatorium15
- sanctum15
- sanitarium15
- sanitorium15
- sargassum15
- sarmentum17
- scandium17
- scholium18
- sclerotium18
- scriptorium21
- scrotum14
- scrum12
- scum11
- scutellum19
- scutum14
- seaborgium19
- sebum12
- secundum18
- sedilium14
- sedum10
- selenium14
- sempervivum29
- sensillum16
- sensorium14
- sensum11
- septarium16
- septum13
- sequestrum24
- serum9
- sestertium14
- silicium16
- simulacrum22
- sistrum11
- skellum17
- skookum19
- slum9
- slumgum18
- smeddum16
- sodium11
- solanum13
- solarium13
- solatium13
- solum10