Namewise

Cillian vs Tadhg

Cillian and Tadhgcompared 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 Tadhg #99 among boys in Northern Ireland.

  • Republic of Ireland · Boys

    In 2025, Cillian was ranked #9 and Tadhg #8 among boys in Republic of Ireland.

  • Scotland · Boys

    In 2024, Cillian was ranked #83 and Tadhg #307 among boys in Scotland.

  • England and Wales · Boys

    In 2025, Cillian was ranked #217 and Tadhg #412 among boys in England and Wales.

Cillian and Tadhg over time

Cillian and Tadhg appear together in 3 published lists, across 106 years of shared records. Cillian held the stronger position in more years in 3 of them, Tadhg in 0.

In none of those lists did their order change and stay changed.

Tadhg reached its own highest recorded position earlier in 1 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.

  • Repeatedly exchanged positions

    Cillian and Tadhg changed places 16 times in Republic of Ireland · Boys between 1970 and 2025, ending at #9 and #8.

  • Closest over the longest run

    Across 55 shared years in Republic of Ireland · Boys, Cillian and Tadhg averaged 25.2 places apart, ending at #9 and #8.

  • Longest-running competitions

    Cillian and Tadhg were both ranked in England and Wales · Boys for 30 years, from 1996 to 2025, ending at #217 and #412.

  • Peaked in the same years

    Both reached their highest recorded position in England and Wales · Boys within 2 years — Cillian #177 in 2024, Tadhg #406 in 2024.

List by list

  • Republic of Ireland · Boys55 shared years, 1970–2025

    Cillian held the stronger position in 45 of those years, Tadhg in 10.

    Highest recorded here: Cillian #4 in 2024, Tadhg #6 in 2024.

    The order between them never changed and held in this list.

    Most recent shared year, 2025: Cillian #9, Tadhg #8.

  • England and Wales · Boys30 shared years, 1996–2025

    Cillian held the stronger position in 20 of those years, Tadhg in 9.

    Highest recorded here: Cillian #177 in 2024, Tadhg #406 in 2024.

    The order between them never changed and held in this list.

    Most recent shared year, 2025: Cillian #217, Tadhg #412.

  • Northern Ireland · Boys21 shared years, 2001–2024

    Cillian held the stronger position in 21 of those years, Tadhg in 0.

    Highest recorded here: Cillian #2 in 2024, Tadhg #81 in 2023.

    The order between them never changed and held in this list.

    Most recent shared year, 2024: Cillian #2, Tadhg #99.

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 Cillian

Pairs where Cillian shares a published list with another name, each measured inside one registrar's own list.

Other comparisons involving Tadhg

Pairs where Tadhg shares a published list with another name, each measured inside one registrar's own list.

Other pairs with the same kind of relationship

Pairs that qualify under the same rule as this one — repeatedly exchanged positions.

All repeatedly exchanged positions→

Other pairs from Republic of Ireland lists

Pairs measured inside Republic of Ireland's own published lists, where this pair's strongest relationship is also recorded. Positions in these lists are not comparable with another registrar's.

Republic of Ireland overview→

Other pairs ranked together in the 2020s

Pairs both ranked in the same published list at some point between 2020 and 2029.

The 2020s across all registrars→

Side by side

Side-by-side comparison of Cillian, Tadhg
FieldCillianTadhg
Record typeEditorially researched profileEditorially researched profile
Gender usagemalemale
MeaningProbably from Old Irish 'cell' (church) combined with a diminutive suffix.Traditionally interpreted as 'poet'.
OriginIrishIrish
PronunciationNot yet recorded/ˈtˠəiɡ/
Syllables21
Common variants / nicknamesNot yet recordedNot yet recorded
Recorded regional usageGB-ENW, GB-NIR, GB-SCT, IEGB-ENW, GB-NIR, GB-SCT, IE
Most recent popularity observationRepublic of Ireland · Boys #9 (2025)Republic of Ireland · Boys #8 (2025)
Pronunciation clarity (demonstration score)Not yet recorded90/100
Spelling simplicity (demonstration score)82/10094/100
International familiarity (demonstration score)100/100100/100
Data Confidencemediummedium

What the data shows

  • Both Cillian and Tadhg share a recorded Irish origin.
  • Cillian has 2 syllables, compared with 1 for Tadhg.
  • Cillian's recorded meaning differs from Tadhg'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

  1. 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

  2. Highest recorded1997–2024

    Highest recorded position: #2 among boys in Northern Ireland, in 2024 (recorded 1997–2024).

    Northern Ireland · Boys

  3. Most recent2025

    Most recently recorded at #217 among boys in England and Wales, in 2025.

    England and Wales · Boys

Tadhg

Popularity journey

  1. First recorded1965

    First recorded at #222 among boys in Republic of Ireland in 1965 — the earliest year that source publishes this name, not necessarily the earliest it was used.

    Republic of Ireland · Boys

  2. Highest recorded1965–2025

    Highest recorded position: #6 among boys in Republic of Ireland, in 2024 (recorded 1965–2025).

    Republic of Ireland · Boys

  3. Most recent2025

    Most recently recorded at #412 among boys in England and Wales, in 2025.

    England and Wales · Boys