China 
Africa 
- Conflagration
- Conflation
- Conflict resolution strategy
- Confluence
- Confluency
- Confluent hypergeometric function
- Confocal
- Confocal microscopy
- Conformal
- Conformal antenna
- Conformal coating
- Conformal geometric algebra
- Conformal geometry
- Conformal map
- Conformal prediction
- Conformance checking
- Conformance testing
- Conformation
- Conformational entropy
- Conformity assessment
- Confounding
- Confusion
- Confusion and diffusion
- Confusion matrix
- Congeners
- Congenital cataract
- Congenital glaucoma
- Congestion games
- Congestion pricing
- Conglomerate
- Congo Red
- Congruence
- Congruence relation
- Congruent
- Conic optimization
- Conic sections
- Conical helix
- Conical intersection
- Conical spiral
- Conical surface
- Coniferyl alcohol
- Conjoint
- Conjoint analysis
- Conjugacy classes
- Conjugate
- Conjugate base
- Conjugate gradient method
- Conjugate priors
- Conjugate transpose
- Conjugate vaccine
- Conjugate variables
- Conjugated
- Conjugated fatty acids
- Conjugated linoleic acid
- Conjugated proteins
- Conjugated system
- Conjugation
- Conjunction fallacy
- Conjunctiva
- Conjunctive query
- Conjunctivitis
- Connected cars
- Connected components
- Connected dominating set
- Connected health
- Connected space
- Connected sum
- Connected-component labeling
- Connecting rod
- Connection
- Connection form
- Connection-oriented
- Connectionism
- Connectionist expert system
- Connectionless
- Connective tissue
- Connectivism
- Connectivity
- Connectomes
- Connexins
- Connexons
- Connotation
- Conradson carbon residue
- Cons
- Conscious sedation
- Consensus
- Consensus clustering
- Consensus forecasts
- Consensus sequences
- ConsensusPathDB
- Consequent
- Conservation areas
- Conservation laws
- Conservation of energy
- Conservation of mass
- Conservatism
- Conservative force
- Conservative system
- Conserved current
- Conserved quantities
- Conserved quantity
- Conserved sequence
- Consignee
- Consignor
- Consistency
- Consistent estimator
- Consistent hashing
- Consolidated
- Consolidation
- Const
- Constant air volume
- Constant angular velocity
- Constant bitrate
- Constant current
- Constant elasticity of substitution
- Constant mean curvature
- Constant of integration
- Constant phase element
- Constant speed drive
- Constant term
- Constantan
- Constants of motion
- Constellation diagram
- Constellation shaping
- Constipation
- Constitutive equations
- Constrained Application Protocol
- Constrained Delaunay triangulation
- Constrained least squares
- Constrained optimization
- Constrained-layer damping
- Constraint graph
- Constraint logic programming
- Constraint programming
- Constraint satisfaction
- Constrictive pericarditis
- Constructability
- Constructed wetlands
- Constructible
- Construction
- Construction 2025
- Construction 3D printing
- Construction aggregate
- Construction communication
- Construction contract
- Construction delay
- Construction engineering
- Construction management
- Construction partnering
- Construction permit