Brennan
Meaning
“Irish surname from O Braonain, traditionally linked to 'sorrow' or 'moisture'”
Popularity, 1890–2024
Shape drawn from US Social Security baby-name records. Brennan peaked in the 2000s and the 2010s in nearly equal measure.
When you meet Brennan
Most people given the name Brennan in the United States are teenagers or young adults today.
Estimated from US Social Security birth registrations and typical lifespans; a rough guide, not a rule.
The Brennan deep dive
Whether you’re naming a baby or exploring your own name’s history, this is a personal letter, not a list: where Brennan 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 Brennan fits with your family’s names and surname.
Where Brennan travels
Irish American · A warm Irish American heritage surname-name.
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