Total births
21
Boys' name · since 1972
Thelonius
Since 1972, U.S. Social Security records show 21 babies named Thelonius, peaking in 2006. See the year-by-year trend, decade totals, and state rankings below, sourced from federal birth data.
- 21
- total births
- 1972–2013
- years on record
- 2000s
- peak decade
- 29%
- born in that decade
Thelonius is not among the current top-ranked boys names; 21 have been recorded since 1972.
Thelonius has 21 recorded births among boys since 1972, per the U.S. Social Security Administration, though it falls outside today's most-used boys names, busiest in the 2000s -- see the year-by-year trends, decade totals, and state-level distribution below, all drawn directly from SSA birth-registration files spanning 1972 to 2013.
- 21 total births
- 1972–2013 years on record
- 2000s peak decade
- 29% born in that decade
Data updated Jul 2026
The verdict
21 boys have been named Thelonius since 1972, peaking in the 2000s, last recorded in 2013.
- 21
- total births
- 1972–2013
- years on record
- 2000s
- peak decade
- 29%
- born in that decade
2000s
Peak decade
29% of everyone ever named Thelonius was born in this single decade.
2006
Single peak year
6 babies were named Thelonius in 2006 - its busiest year on record.
Thelonius's usage pattern, beyond the headline number
Splitting Thelonius's full recorded timeline at 2006, 52% of its total births fall in the more recent half of the record versus 48% in the earlier half -- a fairly even split across the full record. Its quietest year on record was 1972, with just 5 recorded births -- worth weighing against the 2006 peak of 6 to see the full range of the name's swing in popularity.
Thelonius at a glance
Last recorded 2013Peak year
2006
Current rank
Unranked
Active since
1972
Thelonius popularity over time
Annual U.S. births registered with the Social Security Administration · 1972–2013
- Peak year (2006)
- 6
- Annual births at peak, across 42 years of records
Thelonius by decade
Total births in each ten-year window, peak vs trough at a glance
2000s was Thelonius's strongest decade.
6 babies received the name during that ten-year window, about 29% of all-time use.
Thelonius births by decade
Total births in each ten-year window
- 1970s
1970s
5 births
- 1990s
1990s
5 births
- 2000s
2000s
6 births
- 2010s
2010s
5 births
What this shows Peak: 2000s at 6 births (29% of all-time use).
Frequently Asked Questions
How popular is the name Thelonius? ▼
Thelonius has been given to 21 babies in the U.S. since 1972, according to SSA data. Its last appearance in the data was 2013. 6 babies were born in 2006, its single highest year.
When was Thelonius most popular? ▼
Thelonius was most popular in the 2000s decade with 6 total births. The single peak year was 2006.
How long has the name Thelonius been used? ▼
The SSA has tracked Thelonius since 1972 -- 42 years through the most recent 2013 data.
What names are similar to Thelonius? ▼
Names with a similar sound or spelling include Theodore, Theo, Theron, Theadore, and 4 more. These share a common prefix and are also used for boys.
What to do with Thelonius's data
- Thelonius's usage has stayed within range of its 2000s decade-level peak (6 total births) through the 2010s (5) -- a comparatively stable name, not a fading trend.
- Weighing it against an alternative? Put two names side by side. Compare names
Figures reflect SSA-reported births only; see the methodology above for the privacy-suppression floor.
Keep exploring Thelonius
Nearby Names Like Thelonius
Names with a similar sound, spelling, or feel to Thelonius
Theodore Boy
#4 317,206 births
Theo Boy
#80 35,830 births
Theron Boy
#2837 12,960 births
Theadore Boy
#9912 4,005 births
Theophilus Boy
#2213 2,448 births
Compare Thelonius side by side: Thelonius vs Theodore Thelonius vs Theo Thelonius vs Theron
Related Names
Names with a similar number of total births
Data Sources
Data as of July 2026. Source: U.S. Social Security Administration (SSA).
According to the Social Security Administration, this profile draws directly from the agency's public-use baby-name files (updated June 2026). See our methodology for the full extraction, aggregation, and privacy-suppression rules.
Primary: Source: U.S. Social Security Administration, Baby Names from Social Security Card Applications, National Data, 1972–2013 (ssa.gov/oact/babynames).
State-level: Source: U.S. Social Security Administration, Baby Names, State-Level Files (namesbystate.zip).
Cite this page
NameAlmanac Editorial. "Thelonius: Baby Name Since 1972 - 21 Births, Peak 2006." NameAlmanac. Accessed via https://namealmanac.com/name/thelonius. Licensed CC BY-SA 4.0.
Name Almanac is rendered directly from the Social Security Administration's public baby-name files, no number is typed in by an editor. This profile for Thelonius draws directly on SSA national and state-level files, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of July 2026.