Cassidy vs Alastair

Baby Name Comparison — 2026

Cassidy

Boy #2,323 Most Popular 3 Syllables

"curly-haired"

Origin: Irish Gaelic

Irish American English

✓ All Clear

Boy #2,390 Most Popular 3 Syllables

"defender of men"

Origin: Greek via Scottish Gaelic

Scottish Irish British American

✓ All Clear

Cassidy Rank #2,323

Alastair Rank #2,390

Cassidy is more popular, ranked #2323 vs #2390 for Alastair.

Is Cassidy or Alastair more popular?

Cassidy is more popular, ranked #2323 compared to Alastair at #2390 in the United States.

What do Cassidy and Alastair mean?

Cassidy means "curly-haired" (Irish Gaelic origin). Alastair means "defender of men" (Greek via Scottish Gaelic origin).

Are Cassidy and Alastair boy or girl names?

Cassidy is primarily a boy name. Alastair is primarily a boy name.