Girl Name
Millie
Millie 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.
Millie — a girl name — is an uncommon, standout choice. If Mollie is on your shortlist, Millie belongs in the same conversation.
Millie meaning, origin, and usage
Meaning: Millie has a distinctive sound and evolving modern usage.
Origin: Multiple naming traditions are associated with this name.
Pronunciation: Baby Name Studio pronounces Millie as M·I·L·L·I·E, with 6 letters and a girl usage profile.
Popularity: According to Baby Name Studio's 2026 tracker, Millie is an uncommon, standout choice in the Rare tier.
Millie variants, nicknames, middle names, and sibling names
- Variants and spelling ideas: Milliea, Milliee, Milliey, Milli.
- Nicknames: Mil and M.
- Middle names: Pair Millie with a middle name that balances its substantial sound; start with the Millie middle name generator.
- Sibling names: Mollie, Mallie, Mellie, Milo, Miley — full picks on the sibling names for Millie guide for a cohesive sibset.
- Similar names: Looking for names that sound like Millie? Browse our names like Millie 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 Millie
What does the name Millie mean?
Millie 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 Millie?
The exact origin of Millie is debated, but it has been used across multiple naming traditions.
How do you pronounce Millie?
Millie has 6 letters and is most commonly stressed on the first syllable.
Is Millie a boy's or girl's name?
Millie is primarily used as a girl's name in US records.
How popular is Millie in 2026?
In our 2026 popularity tracker, Millie sits in the Rare tier — an uncommon, standout choice.
What names are similar to Millie?
Names that share Millie's sound and style include Mollie, Mallie, Mellie, Milo, Miley.
What middle names pair well with Millie?
Good middle-name fits for Millie pair an opposite syllable rhythm: if Millie is short, lean longer (e.g. classical or three-syllable middles); if Millie is longer, a one-syllable middle keeps the full name from feeling heavy.
What are good sibling names for Millie?
Sibling names that pair naturally with Millie share its rhythm without rhyming — Mollie, Mallie, Mellie all sit comfortably alongside it on a shortlist.