boy name · Scottish origin
Alasdair
/ AL-us-ter /
Meaning
Alasdair means Defender of the people (Scottish).
Gender
Boy
Origin
Scottish
Pronunciation
AL-us-ter
Popularity
#3850 · U.S. boys (2025)
Popularity of Alasdair in the US, 1880–2025
Alasdair first appears in US records in 1989. It peaked in 2021, when 37 boys were given the name; in 2025 there were 28.
Source: US Social Security Administration.
What does Alasdair mean?
Alasdair is the Scottish Gaelic form of Alexander, “defender of the people.”
Frequently asked questions
What does the name Alasdair mean?
Alasdair means Defender of the people. Alasdair is the Scottish Gaelic form of Alexander, “defender of the people.”
What is the origin of the name Alasdair?
Alasdair is of Scottish origin.
How do you pronounce Alasdair?
Alasdair is pronounced “AL-us-ter.”
Is Alasdair a boy or a girl name?
Alasdair is most commonly used as a boy name.
How popular is the name Alasdair?
In 2025, Alasdair ranked #3850 among boys’ names in the United States, according to U.S. Social Security Administration data.
When was the name Alasdair most popular?
Alasdair was most popular in 2021, when about 37 US babies were given the name that year, according to US Social Security Administration records.