China 
Africa 
- Cardiac reserve
- Cardiac surgery
- Cardinal number
- Cardinal utility
- Cardinality
- Cardiogenic shock
- Cardioid
- Cardiolipin
- Cardiology
- Cardiomegaly
- Cardiomyopathy
- Cardioplegia
- Cardioprotection
- Cardiopulmonary resuscitation
- Cardiorespiratory fitness
- Cardiotocography
- Cardiotoxicity
- Cardiovascular
- Cardiovascular disease
- Cardiovascular physiology
- Cardioversion
- Carditis
- Cards
- Care and maintenance
- Caret
- Cargo
- Cargo aircraft
- Cargo bikes
- Cargo ships
- Caribbean Current
- Carina
- Carmoisine
- Carmustine
- Carnallite
- Carnauba wax
- Carnitine
- Carnosine
- Carnot cycle
- Carnot heat engine
- Carnotite
- Carotene
- Carotid artery stenosis
- Carotid body
- Carotid endarterectomy
- Carotid sheath
- Carotid sinus
- Carotid sinus nerve
- Carotid stenting
- Carpal
- Carpal bones
- Carpal tunnel
- Carpal tunnel syndrome
- Carpenter
- Carpenters
- Carpet
- Carpometacarpal joint
- Carpool
- Carrageenan
- Carrara marble
- Carreau fluid
- Carriage return
- Carrier Ethernet
- Carrier aggregation
- Carrier generation and recombination
- Carrier lifetime
- Carrier recovery
- Carrier scattering
- Carrier wave
- Carrier-Sense Multiple Access with Collision Avoidance
- Carrier-Sense Multiple Access with Collision Detection
- Carrollite
- Carry
- Carry-lookahead adder
- Carry-save adder
- Carry-select adder
- Carry-skip adder
- Carrying capacity
- Carrying cost
- Carsharing
- Cartesian Genetic Programming
- Cartesian coordinate system
- Cartesian coordinates
- Cartesian product
- Cartesian product of graphs
- Cartesian tensor
- Cartilage
- Cartogram
- Cartographic generalization
- Cartography
- Cartons
- Cartosat
- Cartridge
- Cartridge heater
- Carvacrol
- Carvone
- Caryophyllene
- Cas12a
- Cas9
- Casamino acid
- Cascade
- Cascade effect
- Cascade impactor
- Cascading failure
- Cascode
- Case hardening
- Case report
- Case study
- Case-based reasoning
- Case-control study
- Case-hardening
- Casein kinase
- Caseous necrosis
- Cash conversion cycle
- Cash flow
- Casimir effect
- Casing
- Casing head
- Casing string
- Caskets
- Casks
- Casp
- Caspase
- Caspase 2
- Caspase 3
- Caspase-3
- Caspase-8
- Caspase-9
- Caspian Depression
- Cassava
- Cassegrain antenna
- Cassegrain reflectors
- Cassini ovals
- Cassiterite
- Cast iron
- Cast iron pipe
- Cast steel
- Cast stone
- Cast-in-place concrete
- Castability
- Castellated beam
- Caster
- Caster angle
- Casting
- Casting defects
- Castor oil
- Cat's eyes
- CatBoost
- Catabolism
- Catabolite repression
- Cataclasis