| Caballero | Cabby | Cabo | Caboose | Cacik |
| Cadburry | Caddy | Cadence | Cadet | Cadillac |
| Cady | Caesar | Cagan | Cagney | Cain |
| Caine | Cairo | Caius | Cajun | Cajus |
| Caletto | Calgary | Calibus | Calico | Califax |
| Calimero | Chaz | Calvin | Calvino | Calypso |
| Camelot | Cameo | Camero | Cameron | |
| Camillo | Camino | Camiro | Camiros | Campari |
| Campano | Campene | Campino | Campinolo | Campjo |
| Campo | Camu | Camus | Camuso | Can |
| Cand | Candid | Cando | Candon | Candor |
| Candrew | Candy | Cane | Canetto | Canis |
| Canisto | Cano | Canos | Canto | Cantos |
| Cantus | Cap | Capitano | Capo | Capone |
| Capper | Cappo | Caprice | Capricorn | |
| Captain | Captain Jack | Carello | Caramba | Caramello |
| Carat | Carau | Caraun | Carek | Caribou |
| Carino | Carlie | Carlo | Carlos | Carlson |
| Carly | Caro | Carob | Carolos | Carry |
| Carson | Carus | Caruso | Casanova | Cäsar |
| Casbah | Cascha | Cash | Cashmere | Casimir |
| Casino | Caspar | Casper | Cassidy | Cassio |
| Cassius | Castello | Casto | Castor | Castro |
| Cacherat | Cato | Catus | Cavallo | |
| Chacco | Casey | Canuth | Casmir | |
| Caviar | Cay | Cayo | Cedric | Cei |
| Celino | Cembas | Cen | Ceno | Cento |
| Centu | Cenus | Cenzo | Cenzolo | Ceres |
| Ceresto | Cero | Cermo | Cermolo | Cesar |
| Centurio | Cerberus | |||
| Chablis | Chacha | Cha-Cha | Chagall | Chaki |
| Chakin | Chakoty | Chaly | Chalin | Challenger |
| Chamb | Chamber | Chamberlin | Chambray | |
| Chamois | Champion | Chan | Chandar | Chaney |
| Change | Chantill | Chaos | Chap | Chaplin |
| Chapo | Charlie | Charley | Charly | Charo |
| Chasper | Chasty | Chasto | Chaston | Chatty |
| Chaym | Chaymo | Chaymon | Chedano | Cheddar |
| Cheddaro | Cherock | Cheroke | Cheroky | Cherry |
| Cherub | Cheruby | Chess | Chester | Chesto |
| Chestoy | Chevas | Chevato | Chevatau | Chewbacca |
| Chew-Chew | Chewy | Chiaro | Chiaromo | |
| Chibbi | Chibby | Chibo | Chibolo | Chic |
| Chicho | Chico | Chicco | Chicory | Chief |
| Chiffon | Chikos | Chill | Chilly | Chim |
| Chin-Chin | Chio | Chip | Chipmunk | Chipper |
| Chippy | Chips | Chiron | Chipsi | Choco |
| Choclate | Chingy | Chyrakee | Cheego | Chiras |
| Chopin | Chopper | Chorul | Chorus | |
| Chorum | Chosy | Chowder | Chowy | Chris |
| Christer | Christo | Chubby | Chubfish | Chuck |
| Chucky | Chump | Chumpy | Churchill | Chutney |
| Ciao | Cid | Cido | Cidolo | |
| Ciel | Cielo | Cimarron | Cimbo | Cinnamon |
| Circe | Ciros | Cisco | Citron | |
| Cing | Crisou | Connor | ||
| Clarence | Clark | Claude | Claudio | Claudius |
| Claus | Clay | Cleo | Cliff | Clifford |
| Clinch | Clipper | Clive | Clone | Clou |
| Clover | Clown | Clyde | Coburg | Coco |
| Coconut | Codiac | Cody | Coeur | |
| Cognac | Cold | Coldin | Coldino | Colin |
| Colinus | Collin | Collo | Colmar | Columbus |
| Colt | Comet | Como | Compadre | |
| Conan | Condor | Condur | Confetti | Confucius |
| Congo | Conner | Conrad | Conradi | Consul |
| Conwell | Conwelly | Conwello | Cook | Cookie |
| Cooky | Coolio | Coon | Cooper | |
| Copper | Copter | Cordial | Cordo | Corfar |
| Cori | Corky | Corlos | Cormik | Coronado |
| Corry | Corsar | Corso | Cortez | Corvat |
| Corvin | Cory | Cosimo | Cosmic | Cosmo |
| CODA | Cora | |||
| Costa | Coulombe | Count | ||
| Courage | Couscous | Cowboy | Cowy | |
| Cox | Crab | Crabo | Crabolo | Crack |
| Cracker | Cracky | Craft | Cranberry | Crash |
| Crasso | Crassus | Crawford | Crazy | Crazzy |
| Crescent | Cresso | Crick | Cricket | Cricko |
| Crimson | Crischa | Crispie | Crispin | Cristan |
| Cristo | Cristyl | Critter | Crockett | Crocus |
| Cromwell | Crouton | Crowley | Cruiser | |
| Crumb | Crumpet | Crunchy | Crusoe | Cubby |
| Cuckoo | Cuddles | Cuno | Cupcake | |
| Curby | Curious | Curry | Curt | Curtis |
| Cute | ||||
| Cuvier | Cupido | Cyrano | Cyrer | Cyrane |
| Cyrus | Cystan | Cyster | Cyros | Czar |