Meaning not yet researched.
Cillian: US boys given the name each year, 1880 to 2025, from Social Security card applications. 595 in 2025. Its best rank was #463 in 2024.
US births per year · SSA card applications
Peaked at #463 in 2024; #507 in 2025. Every baby recorded as Cillian in 2025 was a boy.
Baby name · US data 1880–2025
#507 for US boys in 2025. Its best year was 2024, at #463.
Hover, tap or use the arrow keys for any year. Years with fewer than five babies of a sex are not published by SSA and show as zero.
Cillian: US boys given the name each year from 1880 to 2025. 595 boys in 2025. Peak: #463 in 2024 · most boys in one year: 668 (2024).
In 2025, 595 US boys were named Cillian, making it the 507th most common boys’ name of the year, down 44 places from #463 in 2024. That is 73 fewer than the 668 boys named Cillian in 2024. Its best rank for boys was #463, reached in 2024. That year also had the most boys given the name: 668. For comparison, it was #1,418 in 2015 and unranked in 1950.
Social Security card records list Cillian in 25 years of the 146 from 1880 to 2025, starting in 1995 with 5 babies. In all, 4,090 US babies have been given the name, 0.1% of them girls and 99.8% boys. Its busiest decade was the 2020s, with 2,668 babies named Cillian.
Over the 10 years from 2016 to 2025, 3,388 US boys were named Cillian; the busiest of those years was 2024, with 668. In 2025 that was about 1 in 2,871 of the boys in SSA’s list for the year.
Among the states, Cillian ranked highest in Alaska in 2025, at #169 for boys there. It was not in the top 100 of any state. Related spellings in the SSA files include Killian (16,834 babies since 1880) and Kylian (3,750 babies since 1880). Rarer spellings such as Zillion and Cilian are summarised on this page.
Meaning not yet researched.
We publish a meaning only with a cited source and a confidence label, and never generate one. Meanings are being researched for the most common names first.
Rare spellings summarised here: Zillion (33), Cilian (5).
Numbers are all-time US births. Links come from Wikidata’s “said to be the same as” (P460, CC0) and our spelling rule: at most two letters different, with the same sound pattern.
No nicknames listed for Cillian in the open dataset we use.
Source: carltonnorthern/nicknames (Apache-2.0).
US boys. Rank within each state. SSA leaves out states where fewer than five boys got the name, so 16 are not listed.
| State | Births 2025 | Rank 2025 | Rank 2015 |
|---|---|---|---|
| Alaska | 5 | #169 | — |
| Rhode Island | 5 | #206 | — |
| Delaware | 5 | #214 | — |
| New Hampshire | 5 | #240 | — |
| New Mexico | 7 | #276 | — |
| Massachusetts | 18 | #310 | — |
| Virginia | 25 | #330 | — |
| New Jersey | 24 | #345 | #875 |
| Colorado | 18 | #348 | — |
| New York | 50 | #353 | #1,082 |
| Ohio | 31 | #358 | — |
| Illinois | 29 | #366 | #1,207 |
| Connecticut | 7 | #391 | #467 |
| Pennsylvania | 26 | #400 | #1,062 |
| Oregon | 9 | #409 | — |
| Washington | 17 | #428 | — |
| North Carolina | 25 | #433 | — |
| Wisconsin | 10 | #491 | — |
| California | 60 | #510 | #1,219 |
| Oklahoma | 8 | #513 | — |
| Minnesota | 10 | #524 | — |
| Tennessee | 14 | #527 | — |
| Missouri | 11 | #527 | — |
| Maryland | 9 | #527 | — |
| Mississippi | 5 | #541 | — |
| Utah | 7 | #571 | — |
| Florida | 29 | #587 | #1,293 |
| Kansas | 5 | #611 | — |
| South Carolina | 7 | #619 | — |
| Indiana | 10 | #629 | — |
| Arizona | 10 | #646 | #800 |
| Texas | 35 | #780 | #2,169 |
| Michigan | 9 | #784 | — |
| Louisiana | 5 | #798 | — |
| Georgia | 9 | #929 | — |
Births and national rank for each year SSA lists the name, newest first.
| Year | Girls | Girls rank | Boys | Boys rank |
|---|---|---|---|---|
| 2025 | — | — | 595 | #507 |
| 2024 | 6 | #13,845 | 668 | #463 |
| 2023 | — | — | 477 | #594 |
| 2022 | — | — | 353 | #736 |
| 2021 | — | — | 341 | #747 |
| 2020 | — | — | 228 | #957 |
| 2019 | — | — | 186 | #1,078 |
| 2018 | — | — | 193 | #1,052 |
| 2017 | — | — | 170 | #1,126 |
| 2016 | — | — | 177 | #1,107 |
| 2015 | — | — | 121 | #1,418 |
| 2014 | — | — | 87 | #1,734 |
| 2013 | — | — | 77 | #1,853 |
| 2012 | — | — | 73 | #1,946 |
| 2011 | — | — | 66 | #2,040 |
| 2010 | — | — | 54 | #2,359 |
| 2009 | — | — | 52 | #2,458 |
| 2008 | — | — | 51 | #2,477 |
| 2007 | — | — | 39 | #2,982 |
| 2006 | — | — | 42 | #2,750 |
| 2005 | — | — | 10 | #7,207 |
| 2004 | — | — | 8 | #8,267 |
| 2001 | — | — | 6 | #9,466 |
| 1999 | — | — | 5 | #10,182 |
| 1995 | — | — | 5 | #9,095 |
About the data: counts are Social Security card applications for US births, for names given to at least five babies of a sex in a year (SSA, names.zip, public domain). Ranks follow SSA’s own order: most births first, ties alphabetical. Files retrieved 2026-10-05 (checksum on our sources page).