Sullivan vs Arlo

Baby Name Comparison — 2026

Sullivan

Boy #340 Most Popular 3 Syllables

"descendant of the dark one"

Origin: Irish Gaelic

Irish American English

✓ All Clear

Boy #146 Most Popular 2 Syllables

"fortified hill"

Origin: Old English

English American Australian

✓ All Clear

Sullivan Rank #340

Arlo Rank #146

Arlo is more popular, ranked #146 vs #340 for Sullivan.

Is Sullivan or Arlo more popular?

Arlo is more popular, ranked #146 compared to Sullivan at #340 in the United States.

What do Sullivan and Arlo mean?

Sullivan means "descendant of the dark one" (Irish Gaelic origin). Arlo means "fortified hill" (Old English origin).

Are Sullivan and Arlo boy or girl names?

Sullivan is primarily a boy name. Arlo is primarily a boy name.