Cillian
KIL-ee-an
Cillian probably derives from Old Irish cell meaning “church” combined with a diminutive suffix, producing the sense of “little church” or “associated with a church.”
Saint Cillian (also Killian) was a 7th-century Irish missionary martyred in Würzburg, Germany. His feast day is celebrated on July 8, and he is venerated in both Irish and German Catholic traditions.
Cillian is at its all-time SSA peak: No. 463 in 2024 with 668 births. The name has surged on the back of its most famous modern bearer.
What the name Cillian means
Irish actor Cillian Murphy won the Academy Award for Best Actor in 2024 for Oppenheimer. His sustained fame across Peaky Blinders and 28 Days Later has been the primary driver.
Two syllables - KIL-ee-un - carry a distinctly Irish melody. The hard C (pronounced K) and liquid middle create a name that sounds both ancient and fresh.
The Irish spelling can challenge non-Irish readers who may expect a soft C. Despite this, the name’s popularity shows that American parents are embracing the original form.
As a peak-year name in 2024, Cillian may continue climbing. Murphy’s Oscar win provides the kind of sustained cultural boost that anchors a name for years.
US popularity over time
Numerology and symbolism
Based on Pythagorean numerology — a traditional system linking name letters to numbers. Presented for cultural interest.
Famous people named Cillian
Cillian - similar names
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