Given name
Alastair
“helper and defender of mankind”
Alastair is a form of Alexander. One Greek interpretation is “helper and defender of mankind.”
Meaning & origin
What it means
In Scottish use, Alastair carries the interpretation “helper and defender of mankind.” Alastair is a form of Alexander. One Greek interpretation is “helper and defender of mankind.”
Combines direct and name-family evidence
Where it comes from
An origin associated with this spelling is Scottish.
How it developed
Alastair is used as a form of Alexander.
The story
Published U.S. birth records include this spelling as early as 1922. This is the earliest published observation available here, rather than a date for the name’s origin.
From dated birth records
Alastair through the years
- Babies since 1880
- 1,364
- 1,364 boys · 0 girls
- Most popular year
- 2025
- 67 babies
- 2025
- 67
- #2,147 for boys
- 2021–25 vs 2016–20
- +15%
- Rising
Where it’s given
By the numbers
In 2025, this name appeared in 67 U.S. birth records for boys, ranking No. 2,147 among boys’ names. Average annual use for boys was 15.1% higher in 2021–2025 than in 2016–2020. In 2025, Texas had the largest reported state-level birth count for boys with this name (7). Published U.S. population figures for this spelling include 1,560 as a first name in 2020.
From Social Security birth records and U.S. Census name counts for this exact spelling. Other spellings are counted separately.
Alastair’s family of names
In English usage, Alastair has a diminutive in Al. In English usage, Alastair shares an earlier linguistic root with Alexander. Alastair has a related form in Allie.
Inner ring: nicknames and forms · outer: across languages.
Around the world
Alastair has relatives in 4 languages.
6 related names in 4 languages. Point at a dot, or tab to the map and use the arrow keys.
Nicknames & forms 33
Diminutives, pet forms, short forms and variants used alongside the name.
- Allievariant
- Alistairvariant · English
- Alistervariant
- Allyvariant
- Alastorvariant
- Aleistervariant · English
- Allistervariant
- Alasdairvariant · Scottish Gaelic
Show 25 moreShow fewer
- Allivariant
- Alastervariant
- Alistarvariant
- Aldiminutive · English
- Alleevariant
- Alleyvariant
- Allistairvariant
- Alystervariant
- Alleavariant
- Allastairlikely variant
- Alystairvariant
- Alysdarevariant
- Alysdairvariant
- Allystervariant
- Allystairvariant
- Allysdairvariant
- Allistirvariant
- Allastirvariant
- Allastervariant
- Allaistarvariant
- Alestervariant
- Alaistervariant
- Alaistairvariant
- Alaisdairvariant
- Alasteirvariant
Across languages 2
Equivalents and cognates in other languages, plus older forms it grew from.
People named Alastair
- Al StewartScottish singer-songwriter, folk-rock musicianborn 1945
- Alastair ReynoldsBritish science fiction author (born 1966)
- Alastair Windsor, 2nd Duke of Connaught and StrathearnMember of the British Royal Family, British Army officer (1914-1943)
- Alastair CookEnglish cricketer (born 1984)
- Alastair McCorquodaleBritish athlete (1925-2009)
- Alastair SimScottish actor (1900–1976)
- Alastair HeathcoteBritish rowerborn 1977
- Alastair G. W. CameronCanadian astrophysicist (1925–2005)
- Alastair DuncanScottish actorborn 1958
Listed by how widely each person is written about, which says nothing about the name itself.
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