Kacy
Feminine · “Irish O Cathasaigh”
Kacy is given to both — 5,049 girls and 998 boys since 1880. See Kacy as a boy nameSee other names given to both
Casey Jones drove a train into a stalled freight at Vaughan, Mississippi in 1900, stayed at the brake, and was the only person killed. A friend wrote a ballad about it, and the name spread across America. Jones was called Casey after Cayce, Kentucky, the town he grew up in, so the name is a place before it is anything else.
How old is the name Kacy?
Kacy first appears in US birth records in 1956 — 69 years ago. The typical Kacy alive today was born around 1990, making them about 35 years old. About 4,900 people named Kacy are estimated to be alive in the US today.
When was the name Kacy most popular?
Kacy peaked in 1987, reaching #941 nationally. Today it ranks #8362, 7,421 places below that high. See the whole 1987 chart.
Where it comes from
From O Cathasaigh to Kacy
The story of Kacy
The ballad was written by Wallace Saunders, an engine wiper who had worked with Jones, and it entered oral circulation immediately, was picked up by vaudeville performers, published in several versions and recorded many times. The story it tells is broadly accurate: Jones was running late, took a curve too fast into a freight train that had not fully cleared the main line, sent his fireman to jump, and was found dead with his hand on the brake. What the ballad added was the shape of a folk hero, and the name went with it. Casey entered American use for boys and later for girls, and by the 1980s the female use was substantial. The K respelling belongs to that later period and is one of hundreds produced by the same instinct in the same decade.
Meaningscholars disagree
Irish O Cathasaigh, descendant of the vigilant one
Casey is an Irish surname from O Cathasaigh, containing cathasach, usually read as vigilant or watchful. The American given name owes much of its spread to the railroad engineer John Luther Jones, nicknamed Casey after his home town of Cayce, Kentucky, and to the ballad written after his death in 1900. Kacy is a modern respelling with K and a -cy ending. It peaks in 1987.
How the name formed
- O Cathasaigh
- Casey
- Kacy
Related forms: Casey · O Cathasaigh
Pronouncing Kacy
KAY-see
Two syllables, stress on the first. Identical to Casey, and identical to the letters K and C said in sequence, which is one reason the spelling exists.
Nicknames for Kacy
Moderate
What the data says
146 years of official birth records
The long climb, and where it stands now
The same years in position rather than babies
- First recorded
- 1956
- Most girls named
- 1990196 — the highest on record
- Peak rank
- #941reached in 1987
- Change vs 2024
- −40.0%12 in 2025, from 20
Rank is a position, a count is a headcount, and they move independently — a name can hold its rank while the number of babies behind it falls. Source: U.S. Social Security Administration.
Kacy in other languages
The same name elsewhere
- Casey in English — spelling variant
- O Cathasaigh in Irish — related form
Strongest US states over the last decade: Florida, California.
Kacys among us
people named Kacy are estimated to be alive in the US today
About 1 girl in 133,939 born in 2025 was named Kacy
Estimated from SSA birth records and published actuarial life tables. Method
Spellings of Kacy
- #8362
- Kacy on the 2025 chart
- #853
- counting every spelling
The SSA counts spellings, not names. Kacy went to 12 girls in 2025, but Kaci and Kazi are the same name said out loud. Together the 3 spellings went to 107, which makes it the 853rd most-given girls’ name of the year — 7,509 places above the chart.
- Kaci88
- Kacy12
- Kazi7
About 1 girl in 15,021 born in 2025 was given one of these spellings — against 1 in 133,939 for Kacy itself.
Spellings are grouped by a fixed rule that folds interchangeable English spellings of one sound (ck/k, ph/f, x/ks, a non-initial y for i) and keeps vowels apart, so Sean and Shawn stay separate names. It errs towards splitting: a family here is never larger than the truth. SSA national data, 2025. Method
Is it right for you
What happens to a name after it peaks
The Liane test
Every popular name lives one long story — a climb, a peak, a slow settling back. Kacy's later chapters haven't been written yet, so we borrowed them: Liane climbed just as high around 1959, and its whole arc is on record. Line the two peaks up, and Liane's path sketches the road Kacy is walking now.
Kacy sits in the calm middle of the cycle — neither chasing a wave nor sliding off one. Middle-of-the-cycle names age slowly and predictably.
A scored estimate from 146 years of naming cycles — not a prophecy. Great names outlive statistics. How this is scored
Kacy beside its neighbors
The names ranked closest to Kacy in 2025, in babies rather than position — the bars are to scale.
US girls given each name in 2025.
The trade-off
- It is short, unisex and easy to say.
- The K makes the first consonant unambiguous.
- The Irish surname behind it has a documented meaning.
- Casey is far more common in both sexes.
- The name spells a pair of initials, which invites comment.
- Kacie, Kasey and Kacey all compete.
Nobody names a baby alone.
Put Kacy to the vote.
Add it to a family vote or a couple’s swipe deck — the other person gets one card, a simple answer and room to say why. No app, no account for them.
Only the people you invite can see your list.
Already decided on Kacy? Hide it among decoys and let them guess.
What they receive
Someone added a name to your list
Kacy
Feminine · #8362 in the U.S.
Frequently asked
- How many Kacys are there in the world?
- No country counts the world's names, so there is no worldwide figure — anyone quoting one is estimating. About 4,900 people named Kacy are estimated to be alive in the US today.
- How do you spell Kacy?
- Kacy is one of 3 recorded spellings. Kaci is the more common one — 88 births in 2025 against 12 for Kacy.
- How popular is the name Kacy in 2025?
- Kacy ranks #8362 among US girl names in 2025, with 12 babies given the name.
- How rare is the name Kacy?
- About 1 in every 133,939 US girls born in 2025 was named Kacy — 12 in all.
- Will my child share the name Kacy with classmates?
- Kacy will almost certainly be the only one in school.
Ranked beside Kacy
Names sitting at a similar level of popularity right now.
Lona#8362 · Peggy#8362 · Leda#8362 · Margarette#8362 · Rella#8362 · Evalena#8362 · Vashti#8362 · Nona#8362
Looking for what else is popular rather than what resembles Kacy? See the current top 100.
Choosing between Kacy and another name?
See them side by side — full stats, history and a gentle verdict.
Compare side by sideIn a hurry? Just pick a winner — one tap, no sign-up, and you see how everyone else voted.
Weighing a whole shortlist? Add the rest in the builder, or settle it with a bracket.
Cast your vote
Which one would you pick?
Your gut first, the numbers after — the split shows once you pick.
US figures from the Social Security Administration. 1880–2025. Data & methodology
No advertising trackers and no data sellinghow we handle your dataindependent and founder-run, about Name Battle