Arlo vs Sullivan

Baby Name Comparison — 2026

Arlo

Boy #146 Most Popular 2 Syllables

"fortified hill"

Origin: Old English

English American Australian

✓ All Clear

Boy #340 Most Popular 3 Syllables

"descendant of the dark one"

Origin: Irish Gaelic

Irish American English

✓ All Clear

Arlo Rank #146

Sullivan Rank #340

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

Is Arlo or Sullivan more popular?

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

What do Arlo and Sullivan mean?

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

Are Arlo and Sullivan boy or girl names?

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