| Cynwared | A royal protector of men. |
| Cynwrig | A chief of royal lineage. |
| Cyny | A descendant of the royalty. |
| Cyppa | One who wears a small cap. |
| Cyppel | A dweller by the chapel. |
| Cyrtla | One who wears a tunic. |
| Cyssi | A variant of the name Cecilia. |
| Daduidog | A name of Welsh origin meaning. |
| Daecca | Derived from Latin, meaning 'from the place of the gods' |
| Daeccel | Combination of Gaelic and Latin, meaning 'noble warrior' |
| Daedca | Derived from Greek, meaning 'beloved of the people' |
| Daeddel | Combination of Gaelic and Latin, meaning 'noble protector' |
| Daeddi | Derived from Welsh, meaning 'noble and wise' |
| Daedheah | Combination of Gaelic and Latin, meaning 'noble and just' |
| Daegheard | Derived from Old English, meaning 'battle guardian' |
| Daegla | Derived from Gaelic, meaning 'noble and strong' |
| Daivon | Combination of Latin and Greek, meaning 'divine gift' |
| Dalian | Derived from the city of Dalian. |
| Dalles | Resting Place; Meadow Dwelling |
| Dallys | Resting Place; Meadow Dwelling |
| Dandy | Virility; Brave; Manly |
| Datin | Dairy or Ditch Town |
| Datuidoci | Derived from Latin, meaning 'gift of the gods' |
| Dauid | Beloved, Friend, Favourite |
| Davene | Derived from Welsh, meaning 'noble and fair' |
| Davenja | Combination of Gaelic and Latin, meaning 'noble and victorious' |
| Dayn | A variant of the name Dane or Dean. |
| Deago | A variant of the name Diego or Diago. |
| Dearil | Derived from Old English, meaning 'beloved and loyal' |
| Deaw | Derived from Welsh, meaning 'gift of God' |
| Debson | Combination of Latin and Old English, meaning 'noble and son' |
| Dec | Derived from Latin, meaning 'ten' |
| Degare | Combination of Gaelic and Latin, meaning 'noble and brave' |
| Dehaney | Derived from Old English, meaning 'noble and leader' |
| Delan | From the Alder Grove |
| Deneheard | Combination of Old English and Latin, meaning 'noble and guardian' |
| Denewulf | Derived from Old English, meaning 'noble and wolf' |
| Denic | Derived from Old English, possibly meaning 'valiant' or 'brave' |
| Denston | English surname derived from 'dene' meaning 'valley' and 'ston' meaning 'stone' |
| Deodat | One who Gives to God |