Onyx vs Cassius

Baby Name Comparison — 2026

Onyx

Boy #359 Most Popular 2 Syllables

"black gemstone"

Origin: Greek (onyx)

American

✓ All Clear

Boy #568 Most Popular 3 Syllables

"hollow, empty"

Origin: Latin

English American Roman

✓ All Clear

Onyx Rank #359

Cassius Rank #568

Onyx is more popular, ranked #359 vs #568 for Cassius.

Is Onyx or Cassius more popular?

Onyx is more popular, ranked #359 compared to Cassius at #568 in the United States.

What do Onyx and Cassius mean?

Onyx means "black gemstone" (Greek (onyx) origin). Cassius means "hollow, empty" (Latin origin).

Are Onyx and Cassius boy or girl names?

Onyx is primarily a boy name. Cassius is primarily a boy name.