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This resource focuses on side effects and other terms used in medicines information and assessments of medicines. It does not include terms that are used only rarely, nor does it cover most disease states or technical terms.
How to use EMA’s medical terms simplifier
- You can search for a term or click on a letter below to see terms beginning with that letter.
- Each entry contains a short description. For some, a longer or alternative description is available by selecting the term.
- We use ‘< >’ to indicate alternative or optional wording.
EMA’s medical terms simplifier will be updated periodically. For comments or suggestions, you can use our Medical terms simplifier comments form.
M
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Macrocytosis
enlargement of red blood cells -
Macrophage
a type of white blood cell -
Macula
the central part of the retina at the back of the eye -
Macular oedema
see oedema, macular -
Magnetic resonance imaging (MRI)
technique for detailed scanning of internal organs <using magnetic fields> -
Maintenance (dose, treatment)
<continuing> <ongoing> <subsequent> -
Malabsorption
poor absorption of nutrients from the digestive system -
Malaise
feeling generally unwell -
Malignant
cancerous -
Mania
mental disorder with extreme excitement and overactivity -
Manic episodes
periods of extremely high mood -
Mantle cell lymphoma
an aggressive cancer of a type of white blood cell called B lymphocytes -
Melanoma
a type of skin cancer affecting cells called melanocytes -
Meningitis
inflammation of the membranes that surround the brain and spinal cord -
Metabolites
breakdown products in the body; the substances that <a food> <a medicine> <a chemical> is broken down into -
Metastasis
cancer that has spread from another part of the body -
Metastatic
has spread to other parts of the body -
Methaemoglobinaemia
too much of an abnormal haemoglobin that cannot carry oxygen effectively -
Minimal residual disease
when very few cancer cells remain in the body after treatment -
Mitochondria
the energy-producing components within cells -
Monoclonal antibody
an antibody (a type of protein) designed to recognise and attach to <named antigen> <a specific target> -
Monotherapy
used on its own -
Mortality
death rate -
Mucopurulent
containing mucus and pus -
Mucosa
see mucous membranes -
Mucositis
inflammation of the moist body surfaces -
Mucositis, oral
inflammation of the lining in the mouth <ranging from soreness and redness to severe ulceration> -
Mucous membranes
moist body surfaces, such as the lining of the mouth -
Mucus
a thick bodily fluid for lubrication and protection -
Multiple myeloma
a cancer of the bone marrow -
Multiple sclerosis (MS)
a disease of the brain and spinal cord in which inflammation destroys the protective covering around nerves and damages the nerves -
Multiple sclerosis, primary progressive
gradual start of multiple sclerosis with steady worsening of the disease -
Multiple sclerosis, relapsing-remitting
when the disease causes multiple sclerosis attacks (relapses) followed by periods with milder symptoms (remission) -
Multiple sclerosis, secondary progressive
when relapsing-remitting multiple sclerosis steadily worsens without any improvement -
Muscle relaxants
medicines used to relax muscles <including muscles that help the patient to breathe> -
Muscular atrophy
see atrophy, muscular -
Musculoskeletal
relating to the muscles and bones -
Mutated
changed -
Myalgia
muscle pain -
Myasthenia gravis
a disease causing muscle weakness -
Myelin
protective covering of nerves -
Myeloablative therapy
treatments that destroy the bone marrow -
Myelodysplastic syndromes
when the bone marrow does not make enough healthy blood cells or platelets -
Myeloid
of <in> bone marrow -
Myeloproliferative diseases
<a slow-growing cancer with> production of too many blood cells of a particular type <that can cause blockages> -
Myelosuppression
a condition in which the bone marrow cannot make enough blood cells -
Myocardial infarction
heart attack <because of blockage in blood supply to a part of the heart> -
Myocarditis
inflammation of heart muscle -
Myoclonic seizure
see seizure, myoclonic -
Myopathy
muscle disease causing weakness -
Myopia
near-sightedness or short-sightedness -
Myositis ossificans
abnormal bone growth in the muscle