Thomasin
A feminine form of the name Thomas, derived from the Aramaic meaning "twin".
Name Census estimates that about 58 living Americans carry the first name Thomasin. The name is used almost exclusively for girls. The average person named Thomasin today is around 12 years old, and the year with the single highest number of Thomasin births was 2023 (16 babies).
This page is the full Name Census profile for Thomasin. 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.
For a British comparison, Name Census UK has a UK baby-name profile for Thomasin with official rankings and popularity over time.
Key insights
- • Fewer than 100 living Americans are believed to carry the name Thomasin. It is among the rarest names in the SSA records.
People living today
58
~ 1 in 5,909,558 Americans
Peak year
2023
16 babies that year
Average age
12
years old
2024 SSA rank
#13,303
Tracked since 1963
Popularity
Thomasin: popularity over time
The SSA tracks Thomasin from the 1960s through to the 2020s, spanning 3 decades of birth certificate data. The biggest single decade for the name was the 2020s, with 50 total registrations. The name continues to be given at rates close to its all-time high, suggesting it has not yet fallen out of fashion.
Babies born per year
Decades
Thomasin 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 Thomasin 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 Thomasin
The name Thomasin is a feminine form of the English name Thomas, which itself derives from the Aramaic name Toma meaning "twin". The name Thomas was popularized by the apostle Thomas, one of the twelve disciples of Jesus Christ. Thomas was also known as Didymus, which is the Greek word for "twin".
Thomasin emerged as a feminine variant of Thomas in medieval England, particularly during the 12th to 14th centuries. It is considered an English name, though its origins can be traced back to the Aramaic language spoken in ancient Judea. The variant spellings Thomasine and Thomasina were also used during this period.
One of the earliest recorded examples of the name Thomasin is found in the Canterbury Tales by Geoffrey Chaucer, written in the late 14th century. In the "Tale of the Wyf of Bathe", Chaucer mentions a character named Thomasine. This suggests that the name was in use in medieval England during Chaucer's time.
Throughout history, there have been several notable individuals who bore the name Thomasin. One of the earliest was Thomasine Percyvell (c. 1370 - c. 1437), an English mystic and visionary who wrote spiritual treatises and was considered a holy woman during her lifetime.
Another historical figure was Thomasine von Zirkitz (c. 1504 - 1574), a German noblewoman and writer who authored the first known German-language cookbook, "Ein Sehr Künstliches und Nutzliches Kochbuch" (A Very Artistic and Useful Cookbook), published in 1570.
In the 17th century, Thomasine Christine Gyllembourg (1617 - 1677) was a Danish noble and landowner who played an influential role in the development of agriculture and land management in Denmark.
During the 18th century, Thomasine Ritchie (1744 - 1826) was a Scottish poet and songwriter who composed several popular ballads and songs, including "The Flowers of the Forest" and "The Bonny Broom".
In the 19th century, Thomasine Christine Gyllembourg-Ehrensvärd (1773 - 1856), a Danish novelist and playwright, was a prominent figure in the Golden Age of Danish literature and authored several influential works, including the novel "Rodzinka" (1824).
People
Thomasin + last name combinations
How many people share a full name with Thomasin as the first name? Click a combination below to see the estimate, or search any pairing.
Related
Other names starting with T
Other first names starting with T with a similar number of bearers.
FAQ
Thomasin: questions and answers
How many people in the U.S. are named Thomasin?
Name Census puts the figure at roughly 58 living Americans. We arrive at this by taking every SSA birth registration for Thomasin 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 5,909,558 US residents.
Is Thomasin a common name?
We classify Thomasin as "Very Rare". It ranks above 56.6% of all first names in the SSA dataset by living bearers. Across the full history of the data, 60 babies have been registered with this name.
When was Thomasin most popular?
The single biggest year for Thomasin was 2023, when 16 babies received the name. The fact that the average living Thomasin is about 12 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
What does the SSA popularity chart show?
The chart tracks births, not the number of people alive with the name today. Each point shows how many babies were given the name Thomasin in that year. That makes it useful for spotting when the name rose, peaked, or faded.
Is Thomasin a female name?
Yes, 100.0% of people registered as Thomasin in the SSA data are female. 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.
Is Thomasin still being used today?
Yes. The SSA still recorded Thomasin in 2024, and the page above shows its latest-year rank where available. A name can be well past its peak and still remain in steady use, especially if it built up a large population over earlier decades.
Why can a name have a lot of living bearers even if it is not trendy now?
Because living-bearer counts and current baby-name popularity measure different things. A name like Thomasin can build up a very large population over many decades, even if fewer parents are choosing it now than they did at its peak.
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.
Does every first name have Census demographic data?
No. The public Census first-name release only covers names that met the Bureau's publication rules, so many rarer names in the SSA files do not have a published Census demographic snapshot. In those cases, the page still shows the SSA trend, gender history, and state data.
How many Americans are named Thomasin?
Find out how many Americans are named Thomasin on our sister site HowManyOfMe.org — a quick modern estimate with the living-bearer count front and centre.