Killian
Meaning
Anglicized form of Cillian, also used in France: probably Old Irish cell, "church", with a diminutive suffix (Saint Killian)
The story
Killian is the Anglicized form of the Irish Cillian, a name traced either to ceall, a church or monastic cell, or to an older word for strife, so it holds both the cloister and the fight. It is above all a saint's name. Saint Killian was a seventh-century Irish monk who carried Christianity to Franconia and was martyred at Würzburg, where he is still honored as the city's patron centuries later. The name traveled with Irish missionaries and Irish emigrants and never lost its warmth. Helped along by the actor Cillian Murphy, it has climbed quickly and reads as current as ever in the United States, whichever spelling parents choose. Soft at the front and strong at the finish, Killian carries a wandering saint and a thousand years of Irish faith in three gentle syllables.
Popularity, 1890–2024
Shape drawn from US Social Security baby-name records. Killian peaked in the 2010s and the 2020s in nearly equal measure.
See popularity in Brazil
Popularity in Brazil
220 people · the #23,750 first name in Brazil · about 1 in 1,000,000 · median age 3
Among people named Killian living in Brazil at the 2022 census, more were born in the 2010s than in any other decade.
The census also counted 124 born between 2020 and August 2022, too recent a span to chart.
Source: IBGE, Censo Demográfico 2022
When you meet Killian
Most people given the name Killian in the United States are children or teenagers today. The name belongs to this generation.
Estimated from US Social Security birth registrations and typical lifespans; a rough guide, not a rule.
The Killian deep dive
Whether you’re naming a baby or exploring your own name’s history, this is a personal letter, not a list: where Killian truly comes from, how it traveled, and what a century of records reveals. If you have grown a tree on nametree, it also considers how Killian fits with your family’s names and surname.
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