Killian
KIHL-yuhn
Killian is the Anglicized form of the Irish Cillián, which likely derives from Old Irish cell meaning “church” combined with a diminutive suffix, giving a sense of “little church” or “one devoted to the church.” An alternative theory links it to the
Old Irish ceallach meaning “strife.”
Saint Kilian was a 7th-century Irish missionary who traveled to Franconia (modern Germany) and was martyred in Würzburg around 689. He became the patron saint of Würzburg, and his feast day (July 8) is still celebrated there with a major festival.
What the name Killian means
Killian ranked No. 369 in 2024 with 884 births. It peaked at No. 248 in 2017 with 1,505 births, part of the broader wave of Irish saint names growing in the US.
The character Killian Jones (Captain Hook) in the TV series Once Upon a Time (2012–2018) kept the name in American pop-culture view during its peak years. Actor Cillian Murphy, while using the Irish spelling, also contributes to the name’s visibility.
Three syllables — KIL-ee-an — are strong and distinctly Irish. The double-l spelling is the Anglicized form; the Irish Cillián uses the single-l original.
Parents with Irish heritage who want a saint’s name with genuine historical depth and a strong sound often choose Killian. The -an ending connects it to names like Brendan and Declan.
Related Irish saint names include Cillian, Brendan, Declan, Kieran, and Tiernan. All share the Old Irish ecclesiastical or Celtic root tradition.
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 Killian
Killian - similar names
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