- Adams-Oliver syndrome
- Adams-Stokes syndrome
- Adapalene
- Adaptation
- Adaptation to extrauterine life
- Adaptationism
- Adapter
- Adaptin
- Adaptive Resonance Theory
- Adaptive behavior
- Adaptive clinical trial
- Adaptive design
- Adaptive equipment
- Adaptive immune system
- Adaptive immunity
- Adaptive memory
- Adaptive optics
- Adaptive response
- Adaptogens
- Adaptor proteins
- Adar
- Add on therapy
- Added sugar
- Adderall
- Addiction
- Addiction Severity Index
- Addiction medicine
- Addiction vulnerability
- Addictive behavior
- Addictive disorder
- Addictive personality
- Addison's disease
- Addition polymerization
- Additive effect
- Additive genetic effects
- Additive manufacturing
- Addressin
- Adduction
- Adductor
- Adductor brevis
- Adductor canal
- Adductor hallucis
- Adductor longus
- Adductor longus muscle
- Adductor magnus
- Adductor magnus muscle
- Adductor pollicis
- Adductor pollicis muscle
- Adductor tubercle
- Adducts
- Adefovir
- Adefovir dipivoxil
- Adenine
- Adenine deaminase
- Adenine nucleotide translocator
- Adenine phosphoribosyltransferase
- Adenitis
- Adeno associated virus
- Adeno-associated virus
- Adenoacanthoma
- Adenocarcinoma
- Adenocarcinoma in situ
- Adenocarcinoma of the lung
- Adenohypophysis
- Adenoid cystic carcinoma
- Adenoid hypertrophy
- Adenoidectomy
- Adenoiditis
- Adenoids
- Adenoma
- Adenoma sebaceum
- Adenomatoid tumor
- Adenomatosis
- Adenomatous polyposis coli
- Adenomatous polyps
- Adenomyoma
- Adenomyomatosis
- Adenomyosis
- Adenosarcoma
- Adenosine
- Adenosine 5' phosphosulfate
- Adenosine deaminase
- Adenosine deaminase deficiency
- Adenosine diphosphate
- Adenosine diphosphate ribose
- Adenosine kinase
- Adenosine monophosphate
- Adenosine receptor agonist
- Adenosine receptor antagonist
- Adenosine receptors
- Adenosine triphosphatase
- Adenosinergic
- Adenosquamous carcinoma
- Adenosylmethionine decarboxylase
- Adenotonsillectomy
- Adenoviral keratoconjunctivitis
- Adenoviridae
- Adenovirus
- Adenovirus genome
- Adenylate cyclase
- Adenylate kinase
- Adenylation
- Adenylosuccinate
- Adenylyl cyclase
- Adenylylation
- Adenylyltransferase
- Adequate intake
- Adequate stimulus
- Adherens junctions
- Adhesins
- Adhesion
- Adhesion G protein-coupled receptors
- Adhesion molecules
- Adhesion receptor
- Adhesions
- Adhesive bonding
- Adhesive capsulitis of the shoulder
- Adhesive dentistry
- Adhesives
- Adhyperforin
- Adie syndrome
- Adinazolam
- Adipocyte protein 2
- Adipocytes
- Adipocytokine
- Adipogenesis
- Adipokines
- Adiponectin
- Adipose tissue
- Adipose tissue macrophages
- Adiposity
- Adipsia
- Adjective Check List
- Adjudin
- Adjustable gastric band
- Adjustable pressure-limiting valve
- Adjustment
- Adjustment disorder
- Adjuvant chemotherapy
- Adjuvant radiotherapy
- Adjuvant therapy
- Adjuvants
- Adlercreutzia
- Administrative controls
- Admission note
- Adnexa
- Adnexal mass
- Adnexitis
- Adolescence
- Adolescent and young adult oncology