- Balanced salt solution
- Balanced translocation
- Balanites aegyptiaca
- Balanitis
- Balanoposthitis
- Balantidium coli
- Balapiravir
- Balint syndrome
- Balkan endemic nephropathy
- Balkan nephropathy
- Ball and socket joint
- Ball of the foot
- Baller-Gerold syndrome
- Ballistic training
- Balloon angioplasty
- Balloon catheter
- Balloon dilatation
- Balloon pulmonary angioplasty
- Balloon septostomy
- Balloon sinuplasty
- Balloon tamponade
- Ballooning degeneration
- Balm of Gilead
- Balneology
- Balneotherapy
- Balo's concentric sclerosis
- Baloxavir marboxil
- Balsalazide
- Balsam
- Balsam of Peru
- Baltimore classification
- Bam A
- Bambuterol
- Bamlanivimab
- Bananas
- Band 3
- Band gap
- Band keratopathy
- Bandages
- Bandemia
- Banding
- Banff Classification
- Banisteriopsis caapi
- Bankart lesion
- Bankart repair
- Bannayan-Riley-Ruvalcaba syndrome
- Bapineuzumab
- Bar code medication administration
- Bar domain
- Barbatic acid
- Barbed broach
- Barbed suture
- Barbigerone
- Barbital
- Barbiturate overdose
- Barbiturates
- Barbituric acid
- Bard1
- Bardet-Biedl Syndrome
- Bardoxolone
- Bare area of the liver
- Bare lymphocyte syndrome
- Bare metal stent
- Bare-metal stent
- Barefoot
- Bariatric surgery
- Bariatrics
- Baricitinib
- Baricity
- Baritosis
- Barium
- Barium enema
- Barium hydroxide
- Barium meal
- Barium sulfate
- Barium sulfate suspension
- Barium swallow
- Bark scale
- Barnes maze
- Baroreceptor reflex
- Baroreceptors
- Baroreflex
- Baroreflex activation therapy
- Barostat
- Barotrauma
- Barr body
- Barratt Impulsiveness Scale
- Barrel chest
- Barrett's esophagus
- Barrier analysis
- Barrier contraception
- Barrier cream
- Barrier nursing
- Barrier to autointegration factor
- Bart syndrome
- Barth syndrome
- Barthel Index
- Bartholin gland
- Bartholin gland carcinoma
- Bartholin's cyst
- Bartholin's gland
- Bartonella
- Bartonella henselae
- Bartonella quintana
- Bartonellosis
- Bartter syndrome
- Basal
- Basal body
- Basal body temperature
- Basal cell
- Basal cell adenoma
- Basal cell carcinoma
- Basal cell nevus syndrome
- Basal cistern
- Basal cisterns
- Basal forebrain
- Basal ganglia disease
- Basal lamina
- Basal layer
- Basal metabolic rate
- Basal plate
- Basal rate
- Basal vein
- Basal-cell carcinoma
- Base analog
- Base dissociation constant
- Base excess
- Base excision repair
- Base pairing
- Base rate
- Base rate fallacy
- Basement membrane
- Basement membrane zone
- Basic airway management
- Basic anxiety
- Basic fibroblast growth factor
- Basic helix-loop-helix
- Basic helix–loop–helix
- Basic life support
- Basic metabolic panel
- Basic reproduction number
- Basic rest-activity cycle
- Basicranium
- Basidiobolomycosis
- Basidiobolus
- Basigin
- Basilar artery
- Basilar invagination
- Basilar membrane
- Basilar plexus