| Cusco | Cusco |
| Cutting Crew | Cutting Crew |
| Cy Young-prisen | Cy Young Award |
| Cyan | Cyan |
| cyanat | cyanate |
| cyanid | cyanide |
| Cyankalium | Cyanide |
| Cyanobakterie | Cyanobacteria |
| Cyberpunk | Cyberpunk |
| Cycle cross | Cyclo-cross |
| Cycling Manager-serien | Pro Cycling Manager |
| Cyclizin | Cyclizine |
| Cyclops | Cyclops |
| Cyclotrimethylenetrinitramine | RDX |
| Cygwin | Cygwin |
| Cykas | Cycas |
| cykel | bicycle |
| Cykelbud | Bicycle messenger |
| cykelhjelm | bicycle helmet |
| Cykellygte | Bicycle lighting |
| cykelsti | cycle path |
| cykle | cycling |
| Cykling | Cycling |
| cyklist | cyclist |
| cyklon | cyclone |
| Cyklonen Sidr | Cyclone Sidr |
| cyklus | cycle |
| Cylinder | Cylinder |
| cylindrisk | cylindrical |
| Cylindrisk koordinatsystem | Cylindrical coordinate system |
| Cyllene | Cyllene |
| Cyndi Lauper | Cyndi Lauper |
| Cynofobi | Fear of dogs |
| Cynosura | Cynosura |
| Cynthia Nixon | Cynthia Nixon |
| Cypern | Cyprus |
| Cyperns flag | Flag of Cyprus |
| Cyperns nationalvåben | Coat of arms of Cyprus |
| Cypres | Cupressus |
| Cypres-familien | Cupressaceae |
| Cypress Hill | Cypress Hill |
| Cyprian Kamil Norwid | Cyprian Norwid |
| Cyprianus | Cyprian |
| cypriotisk | Cypriot |
| cyste | cyst |
| cystein | cysteine |
| Cystisk fibrose | Cystic fibrosis |
| Cytidindifosfat | Cytidine diphosphate |
| Cytidinmonofosfat | Cytidine monophosphate |
| Cytidintrifosfat | Cytidine triphosphate |
| cytologi | cytology |
| Cytoplasma | Cytoplasm |
| Cytosin | Cytosine |
| Cytoskelet | Cytoskeleton |
| cytotoksisk effekt | cytotoxicity |
| Czesław Miłosz | Czesław Miłosz |
| Czesław Słania | Czesław Słania |
| Częstochowa | Częstochowa |
| Cádiz CF | Cádiz CF |
| Câmpia Turzii | Câmpia Turzii |
| Cæsar | Caesar |
| Cæsar Augustus | Augustus |
| Cæsareopapisme | Caesaropapism |
| Cæsarion | Caesarion |
| cæsium | caesium |
| Céline Dion | Celine Dion |
| César Franck | César Franck |
| cøliaki | coeliac disease |
| cølibat | celibacy |
