Fionn vs Oisín
Fionn and Oisíncompared 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.
Republic of Ireland · Boys
In 2025, Fionn was ranked #6 and Oisín #5 among boys in Republic of Ireland.
Fionn and Oisín over time
Fionn and Oisín appear together in 1 published list, across 8 years of shared records. Oisín held the stronger position in more years in 1 of them, Fionn in 0.
In none of those lists did their order change and stay changed.
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.
List by list
Republic of Ireland · Boys8 shared years, 2018–2025
Fionn held the stronger position in 3 of those years, Oisín in 5.
Highest recorded here: Fionn #6 in 2023, Oisín #5 in 2023.
The order between them never changed and held in this list.
Most recent shared year, 2025: Fionn #6, Oisín #5.
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.
Where to go next
Comparisons that share a name, a rule or a published list with this one. Each is an existing comparison page with its own evidence — nothing here says these pairs are alike.
Other comparisons involving Fionn
Pairs where Fionn shares a published list with another name, each measured inside one registrar's own list.
- Fionn vs Eoin
Over 51 shared years in Republic of Ireland · Boys, Fionn rose about as far as Eoin fell — from #257 and #65 in 1971 to #6 and #106 in 2025.
Fionn · Eoin · 51 shared years, 1971–2025 · Mirrored each other
- Fionn vs Marcus
Over 51 shared years in Republic of Ireland · Boys, Fionn rose about as far as Marcus fell — from #257 and #107 in 1971 to #6 and #232 in 2025.
Fionn · Marcus · 51 shared years, 1971–2025 · Mirrored each other
- Nicholas vs Fionn
Over 51 shared years in Republic of Ireland · Boys, Fionn rose about as far as Nicholas fell — from #85 and #257 in 1971 to #198 and #6 in 2025.
Nicholas · Fionn · 51 shared years, 1971–2025 · Mirrored each other
- Fionn vs Ronan
Over 51 shared years in Republic of Ireland · Boys, Fionn rose about as far as Ronan fell — from #257 and #49 in 1971 to #6 and #86 in 2025.
Fionn · Ronan · 51 shared years, 1971–2025 · Mirrored each other
Side by side
| Field | Fionn | Oisín |
|---|---|---|
| Record type | Editorially researched profile | Official statistical record (evidence-only) |
| Gender usage | male | male |
| Meaning | Traditionally interpreted as 'white' or 'fair', extending in Old Irish usage to 'bright' and figuratively 'true, just'. Strongly associated with the mythological hero Fionn mac Cumhaill. | Not yet recorded |
| Origin | Irish | Not yet recorded |
| Pronunciation | /ˈfɪn/ | Not yet recorded |
| Syllables | 1 | 1 |
| Common variants / nicknames | Not yet recorded | Not yet recorded |
| Recorded regional usage | GB-ENW, GB-NIR, GB-SCT, IE | IE |
| Most recent popularity observation | Republic of Ireland · Boys #6 (2025) | Republic of Ireland · Boys #5 (2025) |
| Pronunciation clarity (demonstration score) | 90/100 | Not yet recorded |
| Spelling simplicity (demonstration score) | 94/100 | 94/100 |
| International familiarity (demonstration score) | 100/100 | 40/100 |
| Data Confidence | medium | medium |
What the data shows
- Fionn has a recorded origin (Irish); Oisín does not have one recorded yet.
- Fionn and Oisín both have 1 syllable.
- A meaning is recorded for Fionn; Oisín doesn't have one written yet.
- Both names have recorded usage in IE.
How each name got here
Fionn
Popularity journey
First recorded1971
First recorded at #257 among boys in Republic of Ireland in 1971 — the earliest year that source publishes this name, not necessarily the earliest it was used.
Republic of Ireland · Boys
Highest recorded1971–2025
Highest recorded position: #6 among boys in Republic of Ireland, in 2023 (recorded 1971–2025).
Republic of Ireland · Boys
Most recent2025
Most recently recorded at #658 among boys in England and Wales, in 2025.
England and Wales · Boys
Oisín
Popularity journey
First recorded2018
First recorded at #15 among boys in Republic of Ireland in 2018 — the earliest year that source publishes this name, not necessarily the earliest it was used.
Republic of Ireland · Boys
Highest recorded2018–2025
Highest recorded position: #5 among boys in Republic of Ireland, in 2023 (recorded 2018–2025).
Republic of Ireland · Boys
Most recent2025
Most recently recorded at #5 among boys in Republic of Ireland, in 2025.
Republic of Ireland · Boys