Cillian
Cillian is classified as a male given name in our dataset. A first name alone does not establish someone’s gender or preferred form of address.
Confidence describes the weight of the source data, not a measured accuracy rate.
- Verdict
- Male
- Confidence
- Medium (source weight 8 to 63; not an accuracy rate)
- High source frequency in
- United States, Ireland
- US records 1880–2017
- 1,040 male / 0 female
- Data
- nam_dict (GFDL) + US SSA
- Dataset built
- 2026-09-11
How to address Cillian
If you do not know Cillian’s preferred form of address, use a greeting without Mr or Ms: “Dear Cillian,” in English, “Guten Tag Cillian,” in German. Include their family name if you know it. The name’s classification describes its usage. Follow the form of address the person uses for themselves.
Ready-made greetings in six languages
English
Dear Cillian,
German
Guten Tag Cillian,
French
Bonjour Cillian,
Spanish
Estimado/a Cillian:
Chinese
Cillian您好：
Japanese
Cillian様
English
Hi Cillian,
German
Hi Cillian,
French
Salut Cillian,
Spanish
Hola Cillian,
Chinese
Cillian你好：
Japanese
Cillianさん
This is a statistical estimate, not a statement about the gender, identity or correct form of address of any particular person.
Country breakdown
| Country | How common | Usually |
|---|---|---|
| United States | uncommon | man's name |
| Ireland | rare | man's name |
United States birth data
1,040 male · 0 female · 1,040 births recorded
Records from 1980–2017: 100% male.
Frequently asked questions
Is Cillian a male or female name?
Cillian is classified as a male given name in our dataset. A first name alone does not establish someone’s gender or preferred form of address.
How do I address Cillian in an email?
If you do not know Cillian’s preferred form of address, use a greeting without Mr or Ms: “Dear Cillian,” in English, “Guten Tag Cillian,” in German. Include their family name if you know it. The name’s classification describes its usage. Follow the form of address the person uses for themselves.
Is Cillian a unisex name?
Cillian is classified as generally male in the combined dataset. This does not rule out other uses. Our categories describe the sources, rather than a complete survey of everyone with this name.
Related names
Sources
Gender by country: nam_dict, the c't first-names dictionary by Joerg Michael, roughly 44,000 names across 55 countries, licensed GFDL. US frequencies: United States Social Security Administration baby-name data (1880–2017), public domain. Classifications are not measured accuracy rates. Method: how we classify names. Full dataset: data & licences. US source data (babynames). Dataset built 2026-09-11; this is not a new collection date for the source records.
DearWho, "Is Cillian a male or female name?", https://www.dearwho.app/name/cillian. Data: nam_dict (J. Michael, GFDL) and US SSA, built 2026-09-11.
BibTeX
@misc{dearwho_cillian,
title = {Is Cillian a male or female name?},
author = {{DearWho}},
year = {2026},
url = {https://www.dearwho.app/name/cillian},
note = {Data: nam_dict (GFDL), US SSA public domain}
}