Boy Name · Polish Origin
Casimir
Casimir means “Proclamation of peace”. It is a boy's name of Polish origin, and it is rare in the United States today — outside the SSA top 1,000.
Origin and meaning: English Wiktionary (CC BY-SA 4.0). Popularity: US Social Security Administration.
Casimir — a boy name from the Polish tradition — is an uncommon, standout choice. Its meaning, "Proclamation of peace", anchors the name in something deeper than sound alone. If Casimer is on your shortlist, Casimir belongs in the same conversation.
Casimir meaning, origin, and usage
Meaning: Proclamation of peace
Origin: Polish naming roots help connect Casimir to related Polish baby names.
Pronunciation: Baby Name Studio pronounces Casimir as C·A·S·I·M·I·R, with 7 letters and a boy usage profile.
Popularity: According to Baby Name Studio's 2026 tracker, Casimir is an uncommon, standout choice in the Rare tier.
Casimir variants, nicknames, middle names, and sibling names
- Variants and spelling ideas: Casimira, Casimire, Casimiry, Casimi.
- Nicknames: Casi and C.
- Middle names: Pair Casimir with a middle name that balances its substantial sound; start with the Casimir middle name generator.
- Sibling names: Casimer, Casimiro, Cassian, Cayson, Casen — full picks on the sibling names for Casimir guide for a cohesive sibset.
- Similar names: Looking for names that sound like Casimir? Browse our names like Casimir guide for phonetic-neighbor picks.
- Explore more: use the Baby Name Explorer, name search, AI name generator, and Baby Name Studio homepage.
Frequently asked about Casimir
What does the name Casimir mean?
Casimir means "Proclamation of peace" and is of Polish origin. The meaning is recorded in English Wiktionary (CC BY-SA 4.0), and in US records Casimir is used as a boy name.
What is the origin of Casimir?
Casimir originates in Polish naming tradition.
How do you pronounce Casimir?
Casimir has 7 letters and is most commonly stressed on the first syllable.
Is Casimir a boy's or girl's name?
Casimir is primarily used as a boy's name in US records.
How popular is Casimir in 2026?
In our 2026 popularity tracker, Casimir sits in the Rare tier — an uncommon, standout choice.
What names are similar to Casimir?
Names that share Casimir's sound and style include Casimer, Casimiro, Cassian, Cayson, Casen.
What middle names pair well with Casimir?
Good middle-name fits for Casimir pair an opposite syllable rhythm: if Casimir is short, lean longer (e.g. classical or three-syllable middles); if Casimir is longer, a one-syllable middle keeps the full name from feeling heavy.
What are good sibling names for Casimir?
Sibling names that pair naturally with Casimir share its rhythm without rhyming — Casimer, Casimiro, Cassian all sit comfortably alongside it on a shortlist.