Dillyn
Derived from the Welsh name Dylan, it means "great sea" or "born from the waves".
Name Census estimates that about 626 living Americans carry the first name Dillyn. It appears on both sides of the gender split, with 65.0% of registrations being male. The average person named Dillyn today is around 19 years old, and the year with the single highest number of Dillyn births was 2003 (32 babies).
This page is the full Name Census profile for Dillyn. Below you will find a gender breakdown showing how the name splits between male and female registrations, a year-by-year popularity chart stretching back to 1880, decade-level totals, the top US states for this name, its meaning and etymology, and a set of frequently asked questions with data-backed answers.
Key insights
- • Dillyn started out as a boys' name but over the decades crossed over and is now given to girls far more often.
People living today
626
~ 1 in 547,531 Americans
Peak year
2003
32 babies that year
Average age
19
years old
2023 SSA rank
#12,688
Tracked since 1991
Gender
Gender distribution for Dillyn
Dillyn is one of the more evenly split names in the SSA data. Of the 634 total registrations, 412 (65.0%) were male and 222 (35.0%) were female.
Dillyn as a male name
- Ranked #12,688 in 2023
- 5 male births in 2023
- Peak: 1999 (24 births)
Dillyn as a female name
- Ranked #13,878 in 2023
- 6 female births in 2023
- Peak: 2013 (19 births)
Popularity
Dillyn: popularity over time
The SSA tracks Dillyn from the 1990s through to the 2020s, spanning 4 decades of birth certificate data. The biggest single decade for the name was the 2000s, with 265 total registrations. Usage has dropped considerably from its 2000s peak. The most recent decade brought in only a fraction of the registrations that the name once attracted.
Babies born per year
Decades
Dillyn by decade
The table below breaks the full SSA timeline into ten-year windows. Each row shows how many male and female babies were given the name Dillyn during that decade, along with a combined total. This is useful for spotting eras where the name surged or retreated.
Origin
Meaning and history of Dillyn
The name Dillyn is a variant of the Irish name Dillon, which itself is derived from the Old Irish Gaelic words "dill" meaning "great" and "an" meaning "descendant" or "child." The name can be traced back to the ancient Irish clan Ó Diolúin, which originated in County Westmeath, Ireland, during the Middle Ages.
In its earliest recorded forms, the name was spelled as Dillón or Dillún, and it was a common surname among members of the powerful Ó Diolúin clan. Over time, the name evolved and took on various spellings, including Dillyn, as it spread to other parts of Ireland and beyond.
One of the earliest recorded instances of the name Dillyn can be found in the Annals of the Four Masters, a chronicle of medieval Irish history compiled in the 17th century. The annals mention several individuals with the surname Dillon or Dillyn, suggesting the name's long-standing presence in Irish history.
Throughout history, there have been notable individuals who bore the name Dillyn or its variants. In the 16th century, Theobald Dillon (1530-1594) was an Irish soldier and landowner who served as the Lord President of Connaught. Another prominent figure was Sir Lucas Dillon (1588-1628), an Irish politician and soldier who served as a member of the Irish Parliament and fought in the Thirty Years' War.
In the 18th century, John Dillon (1727-1805) was an Irish-American politician and patriot who participated in the American Revolutionary War and served as a delegate to the Continental Congress. Arthur Dillon (1750-1794), a French general of Irish descent, also made a name for himself during the French Revolutionary Wars.
In more recent times, John Dillon (1851-1927) was an Irish nationalist politician and leader of the Irish Parliamentary Party, while James Dillon (1902-1986) was an Irish Fine Gael politician and former Minister for Agriculture.
These are just a few examples of the many individuals throughout history who have borne the name Dillyn or its variants, reflecting the name's deep roots in Irish culture and its enduring significance across various eras and regions.
People
Dillyn + last name combinations
How many people share a full name with Dillyn as the first name? Click a combination below to see the estimate, or search any pairing.
Related
Other names starting with D
Other first names starting with D with a similar number of bearers.
FAQ
Dillyn: questions and answers
How many people in the U.S. are named Dillyn?
Name Census puts the figure at roughly 626 living Americans. We arrive at this by taking every SSA birth registration for Dillyn going back to 1880 and adjusting each cohort for expected survival using CDC actuarial life tables. The result is an age-weighted living-bearer count, not a raw birth total. That works out to about 1 in 547,531 US residents.
Is Dillyn a common name?
We classify Dillyn as "Very Rare". It ranks above 86.6% of all first names in the SSA dataset by living bearers. Across the full history of the data, 634 babies have been registered with this name.
When was Dillyn most popular?
The single biggest year for Dillyn was 2003, when 32 babies received the name. The fact that the average living Dillyn is about 19 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
Is Dillyn a male name?
Yes, 65.0% of people registered as Dillyn in the SSA data are male. You can see the full per-sex comparison in the gender distribution section above, which includes the latest year rank, birth count, and peak year for each sex.
Where does this data come from?
First-name figures come from the Social Security Administration's national baby name files, which cover every name on a birth certificate from 1880 to 2024. Living-bearer estimates layer in CDC actuarial life tables broken out by sex to account for mortality. The population baseline (342,754,338) is the Census Bureau's latest national estimate. You can read the full calculation on our methodology page.