- MTA
- MTA1
- MTA2
- MTBE
- MTHFR deficiency
- MTORC1
- MTORC2
- MTS assay
- MTT assay
- MTTF
- MUC1
- MUNE
- MUTYH-associated polyposis
- MVA85A
- MVTR
- MXenes
- MYB
- MYBL2
- MYC
- MYCL
- MYCN
- MYD88
- MYF5
- MYF6
- MYH7
- MYL2
- MYO7A
- MYOT
- MYT1
- Maalox
- MacConkey agar
- Maceration
- Machado-Joseph disease
- Machine ethics
- Machine learning
- Machine perfusion
- Macitentan
- Maclura pomifera
- Macro domain
- Macroadenoma
- Macroalbuminuria
- Macroautophagy
- Macrobiotic diet
- Macrocephalus
- Macrocephaly
- Macrocyclic compounds
- Macrocytic anemia
- Macrocytosis
- Macrodontia
- Macroglia
- Macroglobulin
- Macroglobulinemia
- Macroglossia
- Macrolide antibiotics
- Macrolides
- Macromolecular assembly
- Macromolecular crowding
- Macromolecules
- Macromonomers
- Macronucleus
- Macronutrients
- Macroorchidism
- Macrophage activation
- Macrophage activation syndrome
- Macrophage colony stimulating factor
- Macrophage colony-stimulating factor
- Macrophage elastase
- Macrophage inflammatory protein
- Macrophage migration inhibitory factor
- Macrophage polarization
- Macrophage-activating factor
- Macrophages
- Macrophagic myofasciitis
- Macrophomina phaseolina
- Macropinosome
- Macroprolactin
- Macropsia
- Macrosatellite
- Macrosomia
- Macrostomia
- Macrotyloma uniflorum
- Macrovascular disease
- Macula densa
- Macula densa cells
- Macula lutea
- Macular
- Macular corneal dystrophy
- Macular degeneration
- Macular edema
- Macular hole
- Macular scarring
- Macular sparing
- Macular telangiectasia
- Maculopapular rash
- Maculopathy
- Mad2
- MadCAM-1
- Madarosis
- Maddox rod
- Madelung's deformity
- Madhu
- Madin-Darby canine kidney cells
- Madurella
- Madurella mycetomatis
- Mafenide
- Maffucci syndrome
- Magainin
- Maggot therapy
- Magic angle
- Magic angle spinning
- Magic bullets
- Magic number
- Magic syndrome
- Magical thinking
- Magill forceps
- Magnesia
- Magnesium
- Magnesium L-threonate
- Magnesium acetate
- Magnesium bicarbonate
- Magnesium carbonate
- Magnesium chloride
- Magnesium citrate
- Magnesium compounds
- Magnesium glycinate
- Magnesium hydroxide
- Magnesium lactate
- Magnesium orotate
- Magnesium salicylate
- Magnesium silicate
- Magnesium stearate
- Magnesium sulfate
- Magnesium trisilicate
- Magnet therapy
- Magnetic drug delivery
- Magnetic gait
- Magnetic resonance
- Magnetic resonance angiography
- Magnetic resonance cholangiopancreatography
- Magnetic resonance elastography
- Magnetic resonance enterography
- Magnetic resonance microscopy
- Magnetic resonance neurography
- Magnetic resonance spectroscopic imaging
- Magnetic resonance venography
- Magnetic seizure therapy
- Magnetic stirrer
- Magnetic tweezers
- Magnetism
- Magnetization transfer