Caoilainn: Meaning, Pronunciation and Origin
Caoilainn is an Irish girl's name meaning “slender and fair.” Here’s how to say it, where it comes from, and names that go well with it.
Updated November 2026
- Meaning
- Slender and fair
- Gender
- Girl
- English forms
- Keelin
How do you pronounce Caoilainn?
Caoilainn is pronounced KAY-linn. It has two syllables, with the stress on the first.
What does Caoilainn mean?
Caoilainn is an Irish name made up of caol, “slender,” and fionn, “fair,” the same two words that form the name Caoilfhionn. For Caoilfhionn, Woulfe (1923) gives the English form Keelin and records it as the name of an Irish virgin saint venerated on 3 February, called Coelfinnia in Latin.
The Old Irish form of Caoilfhionn was Cáelfind, from cáel, “slender,” and finn, “white, blessed,” and Behind the Name notes that it was the name of several Irish saints. Related names include Caoilinn and Caoileann, as well as the anglicised Keelin.
Sources: Woulfe, Irish Names and Surnames (1923), Behind the Name, Wikipedia.
How popular is Caoilainn in Ireland?
Caoilainn wasn't in the 2025 tables, which list names given to at least three babies. It was last recorded in 2019, when 5 baby girls got the name. It was most popular in 2005, when 12 baby girls were named Caoilainn, No. 300 that year. The most babies got the name in 2012: 16. It first appears in the records in 1997, with 4 baby girls.
See the numbers by year
| Year | Babies | Rank |
|---|---|---|
| 2019 | 5 | No. 621 |
| 2018 | 5 | No. 629 |
| 2017 | 4 | No. 734 |
| 2016 | 3 | No. 868 |
| 2015 | 5 | No. 660 |
| 2014 | 10 | No. 427 |
| 2013 | 6 | No. 587 |
| 2012 | 16 | No. 317 |
| 2010 | 7 | No. 555 |
| 2009 | 5 | No. 641 |
| 2008 | 7 | No. 546 |
| 2007 | 10 | No. 404 |
| 2006 | 8 | No. 431 |
| 2005 | 12 | No. 300 |
| 2001 | 3 | No. 606 |
| 1999 | 3 | No. 528 |
| 1998 | 5 | No. 380 |
| 1997 | 4 | No. 496 |
Caoilainn in Ogham
Ogham is the oldest way of writing Irish. It was carved along the edges of standing stones, mostly between the 4th and 6th centuries, and read from the bottom up. In later tradition each letter was named after a tree or plant. Here’s Caoilainn, letter by letter.
- CColl, hazel
- AAilm, pine
- OOnn, gorse
- IIodhadh, yew
- LLuis, rowan
- AAilm, pine
- IIodhadh, yew
- NNion, ash
- NNion, ash
Write any name in Ogham with our Ogham translator
Names that go with Caoilainn
Questions about Caoilainn
- How do you pronounce Caoilainn?
- Caoilainn is pronounced KAY-linn, with two syllables and the stress on the first.
- What does Caoilainn mean?
- Caoilainn is an Irish girl's name meaning “slender and fair.”
- Is Caoilainn a girl's name or a boy's name?
- Caoilainn is a girl's name.
- What is Caoilainn in English?
- The English form of Caoilainn is Keelin.
Sources: popularity from the Central Statistics Office, table VSA60 (CC BY 4.0). Meaning and origin from Woulfe, Irish Names and Surnames (1923), Behind the Name and Wikipedia. How we research names: our sources. Spotted a mistake? support@babynamesofireland.com