Casyn vs Fergus

Baby Name Comparison — 2026

Casyn

Boy #4,583 Most Popular 2 Syllables

"vigilant, watchful"

Origin: Irish Gaelic

American Irish English

✓ All Clear

Boy #4,453 Most Popular 2 Syllables

"man of vigor"

Origin: Old Irish

Scottish Irish English

✓ All Clear

Casyn Rank #4,583

Fergus Rank #4,453

Fergus is more popular, ranked #4453 vs #4583 for Casyn.

Is Casyn or Fergus more popular?

Fergus is more popular, ranked #4453 compared to Casyn at #4583 in the United States.

What do Casyn and Fergus mean?

Casyn means "vigilant, watchful" (Irish Gaelic origin). Fergus means "man of vigor" (Old Irish origin).

Are Casyn and Fergus boy or girl names?

Casyn is primarily a boy name. Fergus is primarily a boy name.