Sibling names for Cillian
Names that sound like they belong in the same family as Cillian usually share its era. These sister and brother names rose and fell on a similar curve to Cillian, whose busiest decade was the 2020s, and are about as common, so neither child's name will feel dated or unusual next to the other.
Sister names for Cillian
| Name | Meaning | Rank 2025 | Babies, last 5 years | Peak decade |
|---|---|---|---|---|
| Jaylani | #471 | 2,367 | 2020s | |
| Ayra | #939 | 1,307 | 2020s | |
| Scotlyn | #1,412 | 594 | 2020s | |
| Winslow | #1,169 | 618 | 2020s | |
| Dua | #1,060 | 796 | 2020s | |
| Misk | #1,764 | 401 | 2020s | |
| Meilani | #591 | 1,670 | 2020s | |
| Lennon | #214 | 6,595 | 2020s | |
| Aysel | #2,038 | 416 | 2020s | |
| Elianny | #1,460 | 530 | 2020s | |
| Marigold | Mary's gold (flower) | #590 | 1,898 | 2020s |
| Indie | #634 | 2,414 | 2020s |
Brother names for Cillian
Cillian's era
Cillian ranked #507 for boys in 2025, against #1,418 in 2015. Its best year was 2024, at #463. Names that rose and fell with it share its period feel, which keeps the set consistent.
Timeless names that go with any sibling
These names have been used steadily for a hundred years, so they sit comfortably next to a name from any era, Cillian included.
Girls: Elizabeth, Maria, Lydia, Julia, Miriam, Nina. Boys: Samuel, Anthony, Wesley, Vincent, Victor, Oscar.
Same era, but close to Cillian
These names follow Cillian's curve too, but we left them out above because they share a first letter or an ending with Cillian. Some parents like that echo; if you do, start here.
How these were chosen
Each suggestion's share of US babies has followed a curve close to Cillian's since 1880, and its recent number of babies is within about twelve times Cillian's, so the names are in the same league. Names starting with the same letter as Cillian or with the same ending are left out, so the names go together without matching. Spellings of Cillian itself are excluded.