m-VEINES-QOL/Symmodified Venous Insufficiency Epidemiological and Economic Study-Quality of Life/Symptoms
M/R/Gmurmurs, rubs, gallops
M0Cancer has not metastacized
M1Cancer has metastacized
MAAMycotic Aortic Aneurysm
mAbsmonoclonal antibodies
MACmonitored anesthesia care
MACEmajor adverse cardiac event
MACImatrix autologous chondrocyte implant
MACSManual Ability Classification System
MADRSMontgomery–Åsberg Depression Rating Scale
MAFmitral annular flutter
MAGmyelin-associated glycoprotein
MAIMycobacterium avium-intracellulare infection
MALTmucosa-associated lymphoid tissue
MAMCmid-arm muscle circumference
MAPmean arterial pressure
MAPHRmaximum age-predicted heart rate
MAPKmitogen-activated protein kinase
MARmelanoma-associated retinopathy
MARSmolecular absorbents recirculation system
MASCCMultinational Association for Supportive Care
MCFCmiddle cheek fat compartment
MCHmean corpuscular hemoglobin
MCHCmean corpuscular hemoglobin concentration
MCIIminimum clinically important improvement
MCLmucinous cystic lesion
MCMmajor congenital malformation
MCNmucinous cystic neoplasm
mCNVmyopic choroidal neovascularization
MCOTmobile cardiac outpatient telemetry
mCRCmetastatic colorectal cancer
mCRPCmetastatic castration-resistant prostate cancer
MCTmedium‐chain triglyceride
MCTDmixed connective tissue disease
MCVmean corpuscular volume
MDDmajor depressive disorder
MDEminimum detectable effect
MDFMaddrey discriminant function
MDMA3,4-methylenedioxy-methamphetamine
MDSmyelodysplastic syndrome
MECCMinimal Extracorporeal Circulation
MEDmorphine equivalent dosage
MEKmitogen-activated protein kinase kinase
MELASmitochondrial encephalopathy, lactic acidosis, and stroke-like episodes
MELDModel for End Stage Liver Disease
MELSmodular extracorporeal liver support system
MEPmotor evoked potential
mEq/Lmilliequivalents per liter
MERRFmyoclonic epilepsy with ragged red fibers
MERSMiddle East Respiratory Syndrome
MERS-CoVMiddle East Respiratory Syndrome Coronavirus
METMET proto-oncogene, receptor tyrosine kinase
METSMeasurement of Exercise Tolerance before Surgery
MFCmedial femoral condyle
MFCLMedicare Functional Classification Level
MFO-IMPTmultifield optimization intensity-modulated proton therapy
MFSmetastasis-free survival
mg/dLmilligrams per deciliter
MGMTO[6]-methylguanine-DNA methyltransferase
MHCmajor histocompatibility complex
MHOPmental health outpatient services
MICminimum inhibitory concentration
MIDminimal important difference
mIDH1mutant isocitrate dehydrogenase 1
MILDminimally invasive lumbar decompression
MIPmaximal inspiratory pressure
MIrAVRminimally invasive reoperative aortic valve replacement
MIRCTmassive irreparable rotator cuff tear
MIS-Amultisystem inflammatory syndrome in adults
MIS-Cmultisystem inflammatory syndrome in children
mLAPmean left atrial pressure
MLDmanual lymphatic drainage
MMEMorphine Milligram Equivalents
MMFmaxillomandibular fixation
mmHgmillimeter of mercury
MMLVMoloney murine leukemia virus
MMLV-RTMoloney murine leukemia virus reverse transcriptase
MMNmulti-focal motor neuropathy
mmol/Lmillimole per liter
MMSEmini-mental state examination
MMTPMethadone Maintenance Treatment Program
MODQModified Oswestry Disability Questionnaire
MOGmyelin oligodendrocyte glycoprotein
MOHmedication overuse headache
MOImultiplicity of infection
MOLSTmedical orders for life-sustaining treatment
MOSFmultiple organ system failure
MP-NAATmultiplex nucleic acid amplification test
mPCRmultiplex polymerase chain reaction
MPDmyofascial pain-dysfunction
MPFLMedial patellofemoral ligament
MPImyocardial perfusion imaging
MPJMetatarsal Phalangeal Joint
MPKmicroprocessor-controlled prosthetic knee
MPLMedial Patella Luxation
MPLSmultiport laparoscopic surgery
MPNmyeloproliferative neoplasm
MPNSTmalignant peripheral nerve sheath tumor
MR-proADMmid-regional pro-adrenomedullin
MR-SWImagnetic resonance-susceptibility weighted imaging
MRAmagnetic resonance angiography
MRADLmobility-related activity of daily living
MRCmitochondrial respiratory chain
MRCPMagnetic Resonance Cholangiopancreatogram
MRDminimal residual disease
MREmagnetic resonance elastography
MRgFUSMagnetic Resonance Guided Focused Ultrasound
MRImagnetic resonance imaging
MRMModified Radical Mastectomy
MRSAmethicillin-resistant Staphylococcus aureus
MRVmagnetic resonance venogram
MSAmagnetic sphincter augmentation
MSAFPMaternal Serum Alpha-Fetoprotein
MSImicrosatellite instability
MSISmulti-system inflammatory syndrome
MSKCCMemorial Sloan-Kettering Cancer Center
MSLTMultiple Sleep Latency Test
MSSAmethicillin-sensitive Staphylococcus aureus
MTmechanical thrombectomy
MTHFRmethylenetetrahydrofolate reductase
mTORmammalian target of rapamycin
MUAmanipulation under anesthesia
Multi-Dmulti-disciplinary
MuSKMuscle-Specific Kinase
MVAmotor vehicle accident
MVCmaximal voluntary contraction
MVOmicrovascular obstruction
MVRMitral Valve Replacement
MVVMitral Valve Valvuloplasty
MXmetastasis cannot be measured