- Perirhinal cortex
- Perisinusoidal space
- Peristalsis
- Peristaltic waves
- Perisylvian syndrome
- Peritoneal
- Peritoneal cancer
- Peritoneal carcinomatosis
- Peritoneal cavity
- Peritoneal dialysis
- Peritoneal fluid
- Peritoneal mesothelioma
- Peritoneal washing
- Peritoneovenous shunt
- Peritonitis
- Peritonsillar abscess
- Peritrophic matrix
- Peritubular capillaries
- Peritubular myoid cells
- Perivascular epithelioid cell tumor
- Perivascular space
- Periventricular leukomalacia
- Periventricular nucleus
- Perivitelline space
- Periwound
- Perkins Brailler
- Perlecan
- Perls Prussian blue
- Permanent cell
- Permanent makeup
- Permanent pacemaker
- Permanent teeth
- Permanganate
- Permeability
- Permease
- Permethrin
- Permissive cells
- Permissive hypercapnia
- Permissive hypotension
- Permit-to-work
- Permutation test
- Pernicious anemia
- Pernio
- Peroneal muscles
- Peroneus brevis
- Peroneus longus
- Peroxidase
- Peroxidation
- Peroxide
- Peroxide value
- Peroxiredoxin
- Peroxisomal disorders
- Peroxisome proliferator activated receptor alpha
- Peroxisome proliferator-activated receptor delta
- Peroxisome proliferator-activated receptor gamma
- Peroxisomes
- Peroxyacetylnitrate
- Peroxynitrite
- Perpendicular plate
- Perphenazine
- Perrhenate
- Persecutory delusion
- Perseveration
- Perseverative cognition
- Persimmons
- Persistent fetal circulation
- Persistent generalized lymphadenopathy
- Persistent hyperplastic primary vitreous
- Persistent infection
- Persistent left superior vena cava
- Persistent mullerian duct syndrome
- Persistent organic pollutants
- Persistent pupillary membrane
- Persistent stapedial artery
- Persistent truncus arteriosus
- Persistent vegetative state
- Persister cells
- Person-centered care
- Person-centered therapy
- Person-centred planning
- Person-environment fit
- Person-situation debate
- Persona
- Personal Construct Theory
- Personal distress
- Personal equation
- Personal fable
- Personal health records
- Personal identifier
- Personal life
- Personality
- Personality Assessment Inventory
- Personality assessment
- Personality changes
- Personality development
- Personality disorders
- Personality pathology
- Personality tests
- Personality traits
- Personalized medicine
- Personnel selection
- Perspiration
- Persuasive communication
- Persulfate
- Persulfide
- Pertactin
- Perturbation
- Pertussis
- Pertussis toxin
- Pertussis vaccine
- Pertuzumab
- Pes
- Pes anserinus
- Pes cavus
- Pessary
- Pesticide poisoning
- Pesticide residue
- Pesticide resistance
- Pesticides
- Pestivirus
- Pet radiotracer
- Petasin
- Petasites
- Petechia
- Peters anomaly
- Peters-plus syndrome
- Pethidine
- Petit triangle
- Petitgrain
- Petri dishes
- Petrissage
- Petroleum
- Petroselinic acid
- Petrous bone
- Petrous part of the temporal bone
- Peutz-Jeghers syndrome
- Pevonedistat
- Pexacerfont
- Pexelizumab
- Pexidartinib
- Peyer's patches
- Peyote
- Peyronie's disease
- PfEMP1
- Pfam
- Pfannenstiel incision
- Pfeiffer syndrome
- Pfizer
- Pfizer-BioNTech COVID-19 vaccine
- Pfu DNA polymerase