Callister vs Leo

Baby Name Comparison — 2026

Callister

Boy #43,579 Most Popular 3 Syllables

"defender of men"

Origin: Greek via Gaelic

Scottish Manx Irish

✓ All Clear

Boy #24 Most Popular 2 Syllables

"lion-hearted, brave"

Origin: Latin

English Italian German French American Spanish

✓ All Clear

Callister Rank #43,579

Leo Rank #24

Leo is more popular, ranked #24 vs #43579 for Callister.

Is Callister or Leo more popular?

Leo is more popular, ranked #24 compared to Callister at #43579 in the United States.

What do Callister and Leo mean?

Callister means "defender of men" (Greek via Gaelic origin). Leo means "lion-hearted, brave" (Latin origin).

Are Callister and Leo boy or girl names?

Callister is primarily a boy name. Leo is primarily a boy name.