psilophyton
— Noun
– English
～ any plant or fossil of the genus Psilophyton
Psilopsida
— Noun
– English
～ whisk ferns; comprising the family Psilotaceae or Psilotatae: vascular plants with no roots, partial if any leaf differentiation, and rudimentary spore sacs
psilosis
— Noun
– English
～ a chronic disorder that occurs in tropical and non-tropical forms and in both children and adults; nutrients are not absorbed; symptoms include foul-smelling diarrhea and emaciation
Psilotaceae
— Noun
– English
～ small family of lower ferns having nearly naked stems and minute scalelike leaves
Psilotales
— Noun
– English
～ lower vascular plants having dichotomously branched sporophyte divided into aerial shoot and rhizome and lacking true roots
Psilotatae
— Noun
– English
～ whisk ferns; comprising the family Psilotaceae or Psilotatae: vascular plants with no roots, partial if any leaf differentiation, and rudimentary spore sacs
Psilotum nudum
— Noun
– English
～ pantropical epiphytic or terrestrial whisk fern with usually dull yellow branches and minute leaves; America; Japan; Australia
Psilotum
— Noun
– English
～ type genus of the Psilotaceae
Psithyrus
— Noun
– English
～ a large bee that resembles the bumblebee but lacks pollen-collecting apparatus and a worker caste
Psittacidae
— Noun
– English
～ coextensive with the order Psittaciformes
Psittaciformes
— Noun
– English
～ an order of birds including parrots and amazons and cockatoos and lorikeets and lories and macaws and parakeets
psittacosaur
— Noun
– English
～ primitive dinosaur actually lacking horns and having only the beginning of a frill; long hind limbs and short forelimbs; may have been bipedal
psittacosaurus
— Noun
– English
～ primitive dinosaur actually lacking horns and having only the beginning of a frill; long hind limbs and short forelimbs; may have been bipedal