- Pyelonephritis
- Pyeloplasty
- Pygeum
- Pygmalion effect
- Pyknocytosis
- Pyknosis
- Pylephlebitis
- Pylera
- Pyloric
- Pyloric sphincter
- Pyloric stenosis
- Pyloromyotomy
- Pyloroplasty
- Pyocyanin
- Pyoderma
- Pyoderma gangrenosum
- Pyogenic granuloma
- Pyogenic liver abscess
- Pyometra
- Pyomyositis
- Pyonephrosis
- Pyostomatitis vegetans
- Pyoverdine
- Pyramidal cells
- Pyramidal eminence
- Pyramidal process
- Pyramidal signs
- Pyramidal tract
- Pyramidal tracts
- Pyramidalis
- Pyranocoumarin
- Pyranose
- Pyrantel
- Pyrantel pamoate
- Pyrazinamide
- Pyrazine
- Pyrazinoic acid
- Pyrazofurin
- Pyrazolam
- Pyrazole
- Pyrazolone
- Pyrazolopyrimidine
- Pyrene
- Pyrethroids
- Pyrethrum
- Pyridazine
- Pyridine
- Pyridine alkaloids
- Pyridinoline
- Pyridopyrimidine
- Pyridostigmine
- Pyridoxal
- Pyridoxal 5 phosphate
- Pyridoxal kinase
- Pyridoxal phosphate
- Pyridoxine
- Pyridoxine 5′-phosphate oxidase
- Pyridoxine deficiency
- Pyridoxine-dependent epilepsy
- Pyriform sinus
- Pyrimethamine
- Pyrimidine
- Pyrimidine analogue
- Pyrimidine biosynthesis
- Pyrimidine dimers
- Pyrimidine synthesis
- Pyrimidine-nucleoside phosphorylase
- Pyrin domain
- Pyriproxyfen
- Pyrithione
- Pyrogen
- Pyroglutamate aminopeptidase
- Pyroglutamic acid
- Pyrolysis
- Pyrolytic carbon
- Pyromania
- Pyronaridine
- Pyrophosphatase
- Pyrophosphate
- Pyropoikilocytosis
- Pyroptosis
- Pyrosequencing
- Pyrovalerone
- Pyrrole
- Pyrrolidine
- Pyrrolizidine alkaloids
- Pyrrolnitrin
- Pyrrolobenzodiazepine
- Pyrroloquinoline quinone
- Pyrrolysine
- Pyruvate
- Pyruvate carboxylase
- Pyruvate carboxylase deficiency
- Pyruvate decarboxylase
- Pyruvate dehydrogenase
- Pyruvate dehydrogenase complex
- Pyruvate dehydrogenase deficiency
- Pyruvate dehydrogenase kinase
- Pyruvate kinase
- Pyruvate kinase deficiency
- Pyruvic acid
- Pythiosis
- Pythium
- Pythium insidiosum
- Pyuria
- Q angle
- Q cycle
- Q fever
- Q methodology
- Q wave
- Q-FISH
- Q-type calcium channels
- Q-value
- Q10
- QIIME
- QRISK
- QRS complex
- QS-21
- QT interval
- QT prolongation
- QTC interval
- QTL
- Qigong
- QuEChERS
- Quackery
- Quad helix
- Quadrangular space
- Quadrantanopia
- Quadrantectomy
- Quadrants
- Quadratus femoris
- Quadratus femoris muscle
- Quadratus lumborum
- Quadratus lumborum muscle
- Quadratus plantae
- Quadriceps
- Quadriceps femoris muscle
- Quadriceps tendon
- Quadrigeminal cistern
- Quadrilateral space syndrome
- Quadriparesis
- Quadriplegia
- Quadrupole ion trap
- Qualia
- Qualified Person
- Qualitative methodology
- Quality adjusted life year
- Quality of analytical results
- Quality of life
- Quality of working life