Cillian vs Jason
Cillian and Jasoncompared on official birth-registration statistics and Namewise's recorded data. This page states what each name's record shows — it never picks a winner or scores one name against the other.
Head to head
Ranks are only compared within one published list and one year. Two ranks from different years, from a boys' and a girls' list, or from different registrars are not comparable, so they are not placed side by side.
Northern Ireland · Boys
In 2024, Cillian was ranked #2 and Jason #305 among boys in Northern Ireland.
Republic of Ireland · Boys
In 2025, Cillian was ranked #9 and Jason #135 among boys in Republic of Ireland.
Scotland · Boys
In 2024, Cillian was ranked #83 and Jason #199 among boys in Scotland.
England and Wales · Boys
In 2024, Cillian was ranked #177 and Jason #197 among boys in England and Wales.
Cillian and Jason over time
Cillian and Jason appear together in 3 published lists, across 112 years of shared records. Jason held the stronger position in more years in 2 of them, Cillian in 1.
The order between them changed and held in 3 of those lists — a change in that published list, never a claim that one name displaced the other.
Jason reached its own highest recorded position earlier in 3 of those lists, and Cillian in none. Each position is a place inside its own list, so this compares when they peaked and never how high.
Counted list by list. Two names in the same published list are measured on the same scale in the same year, so those comparisons are real — but positions from different lists are not, so nothing here is combined into an overall standing.
How this pair is related
The relationship kinds these two qualify for, each under its own stated rule. Every one is drawn from a list they both appear in.
- One moved ahead of the other
In 2024, Cillian moved ahead of Jason in England and Wales · Boys — #204 and #174 the year before became #177 and #197.
- Mirrored each other
Over 55 shared years in Republic of Ireland · Boys, Cillian rose about as far as Jason fell — from #305 and #53 in 1970 to #9 and #135 in 2025.
- Longest-running competitions
Cillian and Jason were both ranked in Republic of Ireland · Boys for 55 years, from 1970 to 2025, ending at #9 and #135.
List by list
Republic of Ireland · Boys55 shared years, 1970–2025
Cillian held the stronger position in 22 of those years, Jason in 33.
Highest recorded here: Cillian #4 in 2024, Jason #18 in 1974.
The order changed in 2004: Cillian moved ahead. In 2003 they stood at #60 and #45; by 2004 that had become #40 and #49.
Most recent shared year, 2025: Cillian #9, Jason #135.
England and Wales · Boys29 shared years, 1996–2024
Cillian held the stronger position in 1 of those years, Jason in 28.
Highest recorded here: Cillian #177 in 2024, Jason #69 in 1996.
The order changed in 2024: Cillian moved ahead. In 2023 they stood at #204 and #174; by 2024 that had become #177 and #197.
Most recent shared year, 2024: Cillian #177, Jason #197.
Northern Ireland · Boys28 shared years, 1997–2024
Cillian held the stronger position in 18 of those years, Jason in 10.
Highest recorded here: Cillian #2 in 2024, Jason #36 in 1998.
The order changed in 2007: Cillian moved ahead. In 2006 they stood at #110 and #97; by 2007 that had become #79 and #104.
Most recent shared year, 2024: Cillian #2, Jason #305.
Two names moving past each other in a ranking is a fact about the ranking. Namewise does not claim one name displaced the other, that families chose between them, or that either influenced the other — none of that is in this data.
Side by side
| Field | Cillian | Jason |
|---|---|---|
| Record type | Editorially researched profile | Editorially researched profile |
| Gender usage | male | male |
| Meaning | Probably from Old Irish 'cell' (church) combined with a diminutive suffix. | From Ancient Greek Iason, meaning 'healer'. In Greek mythology, Jason led the Argonauts in the quest for the Golden Fleece; the name also appears in the New Testament as a Hellenized form possibly of a Hebrew name. |
| Origin | Irish | Greek |
| Pronunciation | Not yet recorded | /ˈd͡ʒeɪ.sən/ |
| Syllables | 2 | 2 |
| Common variants / nicknames | Not yet recorded | Not yet recorded |
| Recorded regional usage | GB-ENW, GB-NIR, GB-SCT, IE | AU-NSW, GB-ENW, GB-NIR, GB-SCT, IE, NO, NZ |
| Most recent popularity observation | Republic of Ireland · Boys #9 (2025) | Republic of Ireland · Boys #135 (2025) |
| Pronunciation clarity (demonstration score) | Not yet recorded | 90/100 |
| Spelling simplicity (demonstration score) | 82/100 | 94/100 |
| International familiarity (demonstration score) | 100/100 | 100/100 |
| Data Confidence | medium | medium |
What the data shows
- Cillian is recorded with a Irish origin, while Jason is recorded with a Greek origin.
- Cillian and Jason both have 2 syllables.
- Cillian's recorded meaning differs from Jason's — see the table above for each.
- Both names have recorded usage in GB-ENW, GB-NIR, GB-SCT, IE.
How each name got here
Cillian
Popularity journey
First recorded1970
First recorded at #305 among boys in Republic of Ireland in 1970 — the earliest year that source publishes this name, not necessarily the earliest it was used.
Republic of Ireland · Boys
Highest recorded1997–2024
Highest recorded position: #2 among boys in Northern Ireland, in 2024 (recorded 1997–2024).
Northern Ireland · Boys
Most recent2025
Most recently recorded at #9 among boys in Republic of Ireland, in 2025.
Republic of Ireland · Boys
Jason
Popularity journey
First recorded1964
First recorded at #100 among boys in New South Wales, Australia in 1964 — the earliest year that source publishes this name, not necessarily the earliest it was used.
New South Wales, Australia · Boys
Highest recorded1964–2005
Highest recorded position: #1 among boys in New South Wales, Australia, in 1971 (recorded 1964–2005).
New South Wales, Australia · Boys
Most recent2025
Most recently recorded at #135 among boys in Republic of Ireland, in 2025.
Republic of Ireland · Boys