Castor
How to say it: KAS-tor · /ˈkæstɔːr/
Greek for 'beaver', twin of Pollux in myth - also a bright star in Gemini.
Castor was the 3,853rd most popular boys’ name in the United States in 2025, given to 21 babies (Social Security Administration). The 2020s are its busiest decade so far, its births are up about 18% in ten years, and it is projected to slip to #5,200 by 2030.
Updated · SSA 2025 data, published May 2026 · How we compute these figures
Key facts
| Rank among boys’ names, 2025 | #3,853 |
|---|---|
| Babies born in 2025 | 21 |
| Share of births | 1 in 157,873 |
| Peak decade | 2020s |
| Change over 10 years | +18% |
| Projected rank for 2030 (estimate) | #5,200 |
Sources: Social Security Administration (SSA). How we compute these figures.
Its life, decade by decade
Castor is a newcomer: almost all of its history is from the last forty years.
What goes with it
In the classroom
In a class of 25 children born in 2025, the chance that another child is called Castor is about under 1 in 200.
Around the world
This spelling is used in English, French, Greek, Portuguese, Spanish.
Famous people named Castor
- Castor Cantero (born 1918)Paraguayan footballer
- Castor of Karden (400–400)Priest and hermit
- Castor Paul Msemwa (1955–2017)Roman Catholic bishop
From Wikidata and Wikipedia
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