Baby Name Studio

Girl Name

Casi

Rare · 4 letters

Casi is a girl's name whose meaning is not firmly attested in the historical record. It is used as a girl's name across several naming traditions, and it is rare in the United States today — outside the SSA top 1,000.

Casi is a girl baby name. It currently sits in the Rare tier of US baby names for 2026, and parents who love Casi often also consider Cassi.

Casi meaning, origin, and usage

Meaning: Casi has a distinctive sound and evolving modern usage.

Origin: Multiple naming traditions are associated with this name.

Pronunciation: Baby Name Studio pronounces Casi as C·A·S·I, with 4 letters and a girl usage profile.

Popularity: According to Baby Name Studio's 2026 tracker, Casi is an uncommon, standout choice in the Rare tier.

Casi variants, nicknames, middle names, and sibling names

Frequently asked about Casi

What does the name Casi mean?

Casi has no single meaning that is firmly attested in the historical record. It is used as a girl name in US birth records, and parents usually choose it for its sound rather than a documented meaning.

What is the origin of Casi?

The exact origin of Casi is debated, but it has been used across multiple naming traditions.

How do you pronounce Casi?

Casi has 4 letters and is most commonly stressed on the first syllable.

Is Casi a boy's or girl's name?

Casi is primarily used as a girl's name in US records.

How popular is Casi in 2026?

In our 2026 popularity tracker, Casi sits in the Rare tier — an uncommon, standout choice.

What names are similar to Casi?

Names that share Casi's sound and style include Cassi, Case, Cash, Casey, Casie.

What middle names pair well with Casi?

Good middle-name fits for Casi pair an opposite syllable rhythm: if Casi is short, lean longer (e.g. classical or three-syllable middles); if Casi is longer, a one-syllable middle keeps the full name from feeling heavy.

What are good sibling names for Casi?

Sibling names that pair naturally with Casi share its rhythm without rhyming — Cassi, Case, Cash all sit comfortably alongside it on a shortlist.