| Cillian | Doyle | |
|---|---|---|
| Meaning | Bright-headed; church | dark stranger |
| Origin | Irish | irish |
| Gender | Boy | Boy |
| Pronunciation | KIL-ee-un | DOYL |
| Syllables | 2 | 1 |
| First appeared | 1995 | 0 |
| Peak year | 2024 (668) | 1931 (667) |
| In 2025 | 595 | 0 |
| Trend | Near its peak | Vintage |
Source: US Social Security Administration.
| Decade | Cillian | Doyle |
|---|---|---|
| 2020s | 2,662 | 63 |
| 2010s | 1,204 | 130 |
| 2000s | 208 | 273 |
| 1990s | 10 | 412 |
| 1980s | 0 | 670 |
| 1970s | 0 | 1,462 |
| 1960s | 0 | 3,465 |
| 1950s | 0 | 5,079 |
| 1940s | 0 | 5,529 |
| 1930s | 0 | 6,021 |
| 1920s | 0 | 4,930 |
| 1910s | 0 | 2,054 |
| 1900s | 0 | 216 |
| 1890s | 0 | 87 |
| 1880s | 0 | 9 |
Cillian is linked to “bright-headed” and to cill, “church” or “monastery.”
Anglicized from Irish O Dubhghaill, from 'dubh' meaning 'dark, black' and 'gall' meaning 'stranger, foreigner' — 'dark foreigner', a term historically applied to Viking settlers.
Cillian is more popular than Doyle today: about 595 US babies were given the name Cillian in 2025, compared with 0 named Doyle.
Cillian means Bright-headed; church (Irish origin), while Doyle means dark stranger (irish origin).
In US records, Cillian first appears in 1995 and Doyle in 0, so Doyle has the longer recorded history.