UK boy's name
Castor
One who is diligent and hard-working, from the Greek myth of the twins Castor and Pollux.
For 2026, the newest official UK baby-name figures on this page are from 2022. That release is the current official benchmark rather than a forecast.
Castor is a boy's name in the UK records. People looking for Castor popularity in 2026 should use the latest official release, which is 2022 in this profile. In that release it ranked #3449, with 5 babies registered with the name. Its strongest year in the published records was 2022, with 5 births.
This profile covers 18 England and Wales registrations across 5 recorded years from 2008 to 2022. The figures come from ONS England and Wales, so the page is a view of published baby-name registrations rather than a forecast or a live count of people using the name today.
Castor is at its recorded peak in the England and Wales series.
We estimate that about 18 living people in the UK are called Castor. This uses published birth registrations from England and Wales, Scotland and Northern Ireland, then applies ONS national life tables to estimate how many are likely still alive. It does not forecast extra births for 2023 or 2026.
Key insights
- • Castor ranked #3449 for boys in England and Wales in 2022, with 5 registrations.
- • The name peaked in 2022, when 5 boys were registered as Castor.
- • About 18 living people in the UK are estimated to have Castor as a first name, after adjusting past birth registrations with ONS life tables.
Latest rank (E&W)
#3449
2022
Births in 2022
5
Latest year
Peak year
2022
5 births
Estimated living
18
2026
Meaning
What does Castor mean?
The name Castor has its origins in ancient Greek mythology and language. It is derived from the Greek word "kastor," which means "beaver." The name was borne by one of the twin brothers, known as the Dioscuri, who were the offspring of the god Zeus and the mortal Leda.
In Greek mythology, Castor and his twin brother Pollux were celebrated as the protectors of sailors and travelers. They were associated with the constellation Gemini, and their bright twin stars were believed to guide ships safely across the seas.
The name Castor first appears in Homer's Iliad and Odyssey, where the twin brothers are mentioned as heroes of the Trojan War. In these epic poems, Castor is depicted as a skilled horseman and warrior, renowned for his bravery and loyalty.
One of the earliest recorded individuals with the name Castor was a Roman consul who lived in the 5th century BC. He was part of the influential Castor family and played a significant role in the political affairs of the Roman Republic.
Throughout history, several notable figures have borne the name Castor. One of the most famous was Castor, Duke of Normandy (c. 1165–1238), a French nobleman who served as the regent of Normandy during the minority of Henry III of England.
Another prominent figure was Castor Aguilar (1892–1961), a Mexican revolutionary and military leader who played a crucial role in the Mexican Revolution of 1910-1920.
In literature, one of the most renowned figures with the name Castor was Castor Pollux Cauchemar, a character in the novels of the French author Jules Verne. He was a bold and adventurous explorer who accompanied the protagonists on their fantastic voyages.
The name Castor has also been associated with several scientists and scholars. Castor Durante (1529–1590) was an Italian mathematician and astronomer who made significant contributions to the study of celestial mechanics.
Castor Gonzalez (1917–1983) was a renowned Cuban painter and sculptor, known for his abstract and surrealist works that explored themes of identity and cultural heritage.
While the name Castor has its roots in ancient Greek mythology, it has been used across various cultures and time periods, often associated with individuals who embodied the qualities of strength, bravery, and adventure.
Sourced from namecensus.com.
Popularity
Castor over time
The chart below shows babies named Castor registered in England and Wales in the years where the name appears in the published records, from 2008 to 2022. Empty years are left out so rare names are not stretched across long periods where the published files do not show any registrations.
For Castor, the clearest high point is 2022. The latest England and Wales figure is 5 births in 2022, compared with 5 at the peak.
Babies born per year
Decades
Castor by decade
Decade totals smooth out the yearly jumps and make it easier to see whether Castor was a short-lived spike or a name that stayed in regular use. Average rank is calculated only from years where a published rank exists.
| Decade | Average rank | Total births | Years covered |
|---|---|---|---|
| 2020s | #3449 | 5 | 1 |
| 2010s | #4504 | 10 | 3 |
| 2000s | #4432 | 3 | 1 |
Related
Names similar to Castor
- Charlie 104,761
- Callum 65,796
- Connor 53,072
- Cameron 40,394
- Charles 33,091
- Christopher 26,849
- Caleb 15,553
- Corey 12,622
- Carter 11,505
- Cody 11,075
- Conor 10,298
- Christian 9,695
FAQ
Castor: questions and answers
How popular is the name Castor in the UK right now?
In 2022, Castor was ranked #3449 for boys in England and Wales, with 5 births registered.
When was Castor most popular?
The peak year on record was 2022, with 5 babies registered as Castor in England and Wales.
What is the meaning and origin of Castor?
One who is diligent and hard-working, from the Greek myth of the twins Castor and Pollux.
How many people are called Castor in the UK?
A total of 18 babies have been registered as Castor across the 5 years of ONS England & Wales records shown here.
Which records is this page based on?
The England and Wales timeline uses ONS baby-name records. Scotland figures come from NRS and Northern Ireland figures come from NISRA. Counts are registrations in published baby-name files. The living estimate uses those birth registrations with ONS national life tables.