Noah Boy
NOH-uh
“rest, comfort” · Hebrew
#2
Brennan
BoyIrish· “from an Irish surname”
- Meaning
- from an Irish surname (origin disputed)
- Origin
- Irish
- Pronunciation
- BREH-nuhn
- Syllables
- 2
- US rank 2025
- #1,003
- US babies 2025
- 226
- Best rank
- #242 (2009)
- Peak year
- 2009
Meaning and origin of Brennan
Brennan is often said to mean “from an Irish surname”; the origin is uncertain, though it is usually linked to Irish roots.
Brennan comes from the Irish surname Ó Braonáin, descendant of Braonán. The meaning of Braonán is uncertain; it is often linked to an Irish word for sorrow or for a drop of water, but neither explanation is secure. The Brennan families were long established in the Irish midlands, and emigrants carried the surname to America and Australia. As a first name for boys, Brennan became popular in the United States in the late twentieth century. It has a friendly, athletic feel, similar to Brendan and Brandon. Bren is an easy nickname.
Other spellings with the same sound: Brennen.
Popularity over time
Brennan first appears in US Social Security records in 1916. It has ranked in the top 1,000 in 56 different years, starting in 1966. Its best national rank was #242 in 2009, the same year it reached its highest count of 1,464 babies. In 2025, 226 babies were named Brennan, and it ranked #1,003 nationally. That is 67% fewer than ten years earlier, so it is becoming less common.
Its national rank moved from #3,364 in 1950, #737 in 1980, #276 in 2000, #270 in 2010, and #1,003 in 2025. Of the 33,258 US boys named Brennan since records began, 35% were born in the 2000s, its biggest decade. The 1990s come next, with 8,300 babies. Since 2010, 9,075 more have been named Brennan.
Other boys' names that peaked around the same time include Tyson, Caiden, Aaden, Jonas, and Joaquin.
Where it is most popular (2025)
In 2025, Brennan ranked highest in Louisiana, Arkansas, and Virginia.
Gender, sound and spelling
About 93% of US babies named Brennan over the last 20 years were boys, with a small share of girls.
Brennan is usually pronounced BREH-nuhn, with two syllables. It has seven letters, starts with B and ends in “-an”. Names that sound the same but are spelled differently include Brennen.
Middle names for Brennan
A few middle names that flow with Brennan: each avoids a matching first letter, a rhyme and a vowel clash where the names meet.
Sibling names for Brennan
Similar names
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Lists that include Brennan
Frequently asked questions
What does the name Brennan mean?
Brennan is often said to mean “from an Irish surname”; the origin is uncertain, though it is usually linked to Irish roots.
What is the origin of the name Brennan?
Brennan has Irish roots. Brennan comes from the Irish surname Ó Braonáin, descendant of Braonán.
Is Brennan a popular name?
Not especially. Brennan ranked #1,003 in the US in 2025, which puts it outside the top 1,000.
Is Brennan a boy or girl name?
Brennan is mainly a boy's name. About 93% of US babies named Brennan over the last 20 years were boys, with a small share of girls.
How do you pronounce Brennan?
Brennan is usually pronounced BREH-nuhn. Stressed syllables are in capital letters.
Popularity figures come from US Social Security card applications (names given to at least five babies in a year, 1880 to 2025). How we source names and meanings