1. Process of changing to an inferior state
   - deterioration, declension, worsening

Type of: decline, diminution

• genus Phytelephas
• genus Phytolacca
• genus Phytophthora
• genus Pica
• genus Picea
• genus Pickeringia
• genus Picoides
• genus Picrasma
• genus Picris
• genus Picumnus
• genus Picus
• genus Pieris
• genus Pilea
• genus Pilosella
• genus Pilularia
• genus Pimenta
• genus Pimpinella
• genus Pinckneya
• genus Pinctada
• genus Pineus
• genus Pinguicula
• genus Pinguinus
• genus Pinicola
• genus Pinnotheres
• genus Pinus