China 
Africa 
- Alvimopan
- Alvocidib
- Alzheimer's disease
- Amacrine cells
- Amadori rearrangement
- Amala
- Amalgam
- Amalgam tattoo
- Amanita
- Amanita muscaria
- Amanita phalloides
- Amanita verna
- Amantadine
- Amaranth
- Amaranth oil
- Amaranthus
- Amastatin
- Amatoxin
- Amaurosis
- Ambenonium
- Amber
- Ambidexterity
- Ambient ionization
- Ambiguous genitalia
- Ambiguous loss
- Ambivalent attachment
- Amblyomma americanum
- Amblyopia
- Ambrisentan
- Ambrosia artemisiifolia
- Ambroxol
- Ambulance station
- Ambulances
- Ambulatory assessment
- Ambulatory blood pressure
- Ambulatory care
- Ambulatory glucose profile
- Ambulatory surgery
- Ambystoma mexicanum
- Amebiasis
- Amelanotic melanoma
- Ameloblastic carcinoma
- Ameloblastic fibro-odontoma
- Ameloblastic fibroma
- Ameloblastin
- Ameloblastoma
- Ameloblasts
- Amelogenesis
- Amelogenesis imperfecta
- Amelogenin
- Amenorrhea
- Amenorrhoea
- Amentoflavone
- American Academy of Hospice and Palliative Medicine
- American ginseng
- Americium
- Ames strain
- Ames test
- Amfenac
- Amfepramone
- Amidase
- Amidation
- Amide linkage
- Amides
- Amidines
- Amido black
- Amidoamine
- Amidohydrolase
- Amidophosphoribosyltransferase
- Amidrine
- Amifampridine
- Amifostine
- Amikacin
- Amiloride
- Amination
- Amine oxidase
- Amineptine
- Amines
- Amino acid
- Amino acid analysis
- Amino acid based formulas
- Amino acid metabolism
- Amino acid residues
- Amino acid score
- Amino acid sequence
- Amino acid sequences
- Amino acid substitutions
- Amino acid synthesis
- Amino acid transporter
- Amino acid-based formulas
- Amino acids
- Amino esters
- Amino groups
- Amino methyl phosphonic acid
- Amino sugars
- Amino-acid racemase
- Aminoaciduria
- Aminoacyl tRNA
- Aminoacyl tRNA synthetase
- Aminoacyl-tRNA
- Aminoacylase
- Aminoacylation
- Aminoalcohol
- Aminocaproic acid
- Aminocarb
- Aminoethylpiperazine
- Aminoglutethimide
- Aminoglycoside antibiotics
- Aminoglycosides
- Aminoguanidine
- Aminohippuric acid
- Aminoketone
- Aminolevulinic acid
- Aminolevulinic acid synthase
- Aminomethylphosphonic acid
- Aminooxyacetic acid
- Aminopenicillin
- Aminopeptidase
- Aminopeptidase P
- Aminophenazone
- Aminophylline
- Aminopropionitrile
- Aminopyridine
- Aminorex
- Aminosalicylate
- Aminosalicylic acid
- Aminosteroids
- Aminosugar
- Aminothiazole
- Aminotransferases
- Amiodarone
- Amiodarone induced thyrotoxicosis
- Amisulpride
- Amitraz
- Amitriptyline
- Amivantamab
- Amlexanox
- Amlodipine
- Ammi majus
- Ammi visnaga
- Ammonia
- Ammonia water
- Ammonium
- Ammonium alum
- Ammonium bicarbonate
- Ammonium carbonate
- Ammonium cation
- Ammonium fluoride
- Ammonium formate
- Ammonium hydroxide