Thaddius
A masculine name of Aramaic origin meaning "heart" or "courageous".
Name Census estimates that about 539 living Americans carry the first name Thaddius. The name is used almost exclusively for boys. The average person named Thaddius today is around 37 years old, and the year with the single highest number of Thaddius births was 1989 (18 babies).
This page is the full Name Census profile for Thaddius. 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.
People living today
539
~ 1 in 635,908 Americans
Peak year
1989
18 babies that year
Average age
37
years old
2023 SSA rank
#13,965
Tracked since 1916
Census
Thaddius in the 2020 Census
The 2020 Census recorded 464 people with the first name Thaddius, which placed it at #21,757 in the published first-name tables. This is a snapshot of people who already had the name at the time of the Census.
The SSA sections elsewhere on this page answer a different question: how often parents gave the name to babies over time. The "people living today" figure on this page is different again: it is a current estimate built from SSA birth records and age-based survival rates, so the two numbers are not expected to match exactly.
2020 Census rank
#21,757
National first-name rank
People counted
464
464 in the published race/origin table
Per 100,000
0.2
People with this name in 2020
Largest reported group
Black or African American
52.6% of people with this name
Demographics
Ancestry and ethnicity for Thaddius
In the 2020 Census race and Hispanic-origin table, the largest reported group for people named Thaddius is Black at 52.6%. The next largest groups are White (34.7%) and Hispanic (5.0%). These figures describe the people who had the name in 2020, not any inherent property of the name itself.
The bar chart below shows how people with the first name Thaddius described their own race and ethnicity on the 2020 Census form. The Census Bureau groups responses into six broad categories: White, Black or African American, Hispanic or Latino, Asian and Pacific Islander, American Indian and Alaska Native, and Two or More Races. When a category has too few respondents for a given name, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown so the breakdown is easy to read across every published category. Because the 2020 Census first-name file also includes raw headcounts for each group, Name Census can show those alongside the percentages in the legend and hover tooltip.
Keep in mind that these are self-reported numbers. A first name does not determine a person's race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the name Thaddius at the time of the 2020 Census, not any inherent property of the name itself.
- Black or African American52.6% · 244
- White34.7% · 161
- Hispanic or Latino5.0% · 23
- Two or more races4.7% · 22
- American Indian and Alaska Native2.2% · 10
- Asian and Pacific Islander0.9% · 4
Popularity
Thaddius: popularity over time
The SSA tracks Thaddius from the 1910s through to the 2020s, spanning 12 decades of birth certificate data. The biggest single decade for the name was the 1980s, with 116 total registrations. Usage has dropped considerably from its 1980s peak. The most recent decade brought in only a fraction of the registrations that the name once attracted.
Babies born per year
Decades
Thaddius 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 Thaddius 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 Thaddius
The name Thaddius has its origins in the Aramaic name Taddai, which is thought to be derived from the word "thadd" meaning "breast" or "courageous." It is a variant of the Hebrew name Judah, which means "praised."
The name first appeared in the New Testament of the Bible, where Thaddeus (or Thaddaeus) was one of the twelve apostles of Jesus Christ. He is sometimes identified with Jude the Apostle, who is credited with writing the Epistle of Jude in the New Testament.
One of the earliest recorded individuals with the name Thaddius was Thaddius of Edessa, a Syrian philosopher and theologian who lived in the 4th century AD. He is known for his work in preserving and translating Greek philosophical and scientific texts into Syriac.
In the Middle Ages, there was a Saint Thaddeus (or Thadee) who was a Christian missionary and is recognized as the Apostle of Armenia. He is said to have been martyred in the city of Karin (now known as Erzurum, Turkey) in the 1st century AD.
Another notable figure with this name was Thaddius Hayek (1629-1704), a Lebanese Maronite philosopher, theologian, and writer. He is known for his works on logic, metaphysics, and theology, and his efforts in promoting education in the Maronite community.
In the 18th century, there was Thaddius Kosciuszko (1746-1817), a Polish military leader and national hero who played a significant role in the American Revolutionary War and the Polish-Lithuanian Commonwealth's struggle for independence.
In more recent times, the name Thaddius has been less common, but it has been used as a variant of the names Theodore and Thaddeus. It has maintained its association with courage, strength, and religious significance.
People
Thaddius + last name combinations
How many people share a full name with Thaddius 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
Thaddius: questions and answers
How many people in the U.S. are named Thaddius?
Name Census puts the figure at roughly 539 living Americans. We arrive at this by taking every SSA birth registration for Thaddius 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 635,908 US residents.
Is Thaddius a common name?
We classify Thaddius as "Very Rare". It ranks above 85.3% of all first names in the SSA dataset by living bearers. Across the full history of the data, 593 babies have been registered with this name.
When was Thaddius most popular?
The single biggest year for Thaddius was 1989, when 18 babies received the name. The fact that the average living Thaddius is about 37 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
How common was Thaddius in the 2020 Census?
The published 2020 Census first-name tables recorded 464 people with the name Thaddius, or 0.15 per 100,000 residents. That placed it at #21,757 in the national Census ranking for first names.
Why is the Census count different from the living estimate?
Because they measure different things. The Census figure is a count of people who had the name Thaddius in 2020. The living estimate aims to answer a current question instead: how many people with the name are alive today, based on SSA birth records and age-based survival rates. Since one number is a 2020 snapshot and the other is a present-day estimate, they are not expected to be identical.
What does the Census say about the gender split for Thaddius?
In the 2020 Census sex table, Thaddius appears almost entirely male. Of the 456 people counted with this name, 99.1% were male and only a very small share were female. The Census view is a snapshot of people living with the name in 2020, while the SSA section above tracks births across time.
What does the Census say about the background of people named Thaddius?
In the 2020 Census race and Hispanic-origin table, the largest reported group for people named Thaddius is Black at 52.6%. The next largest groups are White (34.7%) and Hispanic (5.0%). These figures describe the people who had the name in 2020, not any inherent property of the name itself. The percentages in the chart above come from self-reported race and Hispanic-origin responses in the 2020 Census.
Which group reports the name Thaddius most often in the Census?
Black is the largest reported group for people named Thaddius in the 2020 Census, accounting for 52.6% (244 people in the published table).
Why can the Census sex total and race total differ slightly?
The Census Bureau published separate 2020 tables for sex and for race/Hispanic origin, and the released figures can differ slightly because of privacy protection in the public files. That is why this page treats the gender section and the race/origin section as two related snapshots instead of forcing them into one identical total.
Does every first name have Census demographic data?
No. The public Census first-name release only includes names that met the Bureau's publication rules, so many rarer names in the SSA files have no Census demographic snapshot. When that happens, the SSA trend, gender history, and state sections still appear, but the 2020 Census demographic sections are omitted.
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 Thaddius in that year. That makes it useful for spotting when the name rose, peaked, or faded.
Is Thaddius a male name?
Yes, 100.0% of people registered as Thaddius 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.
Is Thaddius still being used today?
Yes. The SSA still recorded Thaddius 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 Thaddius 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.
How many people have Thaddius as a first name?
For a quick modern estimate, our sister site HowManyOfMe.org answers that in one glance, with the living-bearer count front and centre.