Cillian
How to say it: KIL-ee-un · /ˈkɪliən/
From Old Irish 'Cellach' or 'Cillín'; possibly meaning 'bright-headed' or derived from 'ceall' meaning 'church'.
Cillian was the 500th most popular boys’ name in the United States in 2025, given to 595 babies (Social Security Administration). The 2020s are its busiest decade so far, its births are up 4.8-fold in ten years, and it is projected to rise to #245 by 2030.
Updated · SSA 2025 data, published May 2026 · Insee 2025 data, published July 2026 · How we compute these figures
Key facts
| Rank among boys’ names, 2025 | #500 |
|---|---|
| Babies born in 2025 | 595 |
| Share of births | 1 in 5,572 |
| Peak decade | 2020s |
| Change over 10 years | ×4.8 |
| Projected rank for 2030 (estimate) | #245 |
| In France, 2025 | #1,330 among boys’ names, 15 births |
Sources: Social Security Administration (SSA), Insee (France). How we compute these figures.
Its life, decade by decade
New to wide use in recent decades, Cillian crested in the 2020s. Perched at its peak, it appears ready to ascend further.
What goes with it
Three soft syllables with crisp edges create a rolling sound in Cillian. Declan echoes its style.
In the classroom
In a class of 25 children born in 2025, the chance that another child is called Cillian is about under 1 in 200.
Around the world
This spelling is used in English, French, Irish, Scottish Gaelic.
In France: #1,330 for boys in 2025.
England and Wales: #217. Ireland: #9.
Famous people named Cillian
- Cillian Murphy (born 1976)Irish actor
- Cillian Sheridan (born 1989)Irish footballer
From Wikidata and Wikipedia
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