class 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
class 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
Chlamydia psittaci
— Noun
– English
～ bacteria responsible for the sexually transmitted disease chlamydia
C. psittaci
— Noun
– English
～ bacteria responsible for the sexually transmitted disease chlamydia