Theory
- Gender
- Mostly girls
- Say it
- THEER-ee
- Origin
- English
- US rank, 2025
- #5,916 for girls
Theory is a name of English origin, meaning “contemplation, idea”. In 2025 it ranked 5,916th for girls in the US (20 babies).
What does Theory mean?
English: English word, from Greek theoria
“contemplation, idea”
From the English word, which goes back to Greek theoria, 'looking at, contemplation'.
Is Theory a girl's or a boy's name?
In recent years, Theory has been given to girls and boys, mostly girls. In 2025, it was given to 20 girls and 10 boys in the US.
How popular is Theory in the US?
- Rank in 2025
- 5,916th among girls
- Babies in 2025
- 20 about 1 in 80,000 girls
- Five-year trend
- Rising fast up 143% in five years
- Same name in a class
- under 1% chance among 15 girls
In 2025, 20 girls in the US were named Theory, making it the 5,916th most popular name for girls. Five years earlier, in 2020, it was 11,085th. Its busiest year was 2023, with 20 girls. It first appears in the records in 2006. 10 boys were also named Theory in 2025 (7,675th for boys).
Half of all the girls named Theory in the US since 1880 were born between 2016 and 2023, the years shaded on the chart below.
In 2025, 67% of the babies named Theory in the US were girls.
Theory in the US, year by year
| Year | Girls | Rank |
|---|---|---|
| 2025 | 20 | #5,916 |
| 2024 | 16 | #6,928 |
| 2023 | 20 | #5,955 |
| 2022 | 18 | #6,459 |
| 2021 | 18 | #6,409 |
| 2020 | 8 | #11,085 |
| 2019 | 8 | #11,350 |
| 2018 | 7 | #12,459 |
| 2017 | 5 | #15,898 |
| 2016 | 8 | #11,776 |
| 2015 | 7 | #13,001 |
| 2014 | 8 | #11,925 |
| 2013 | 9 | #10,995 |
| 2012 | 8 | #12,193 |
| 2011 | 0 | – |
| 2010 | 0 | – |
| 2009 | 0 | – |
| 2008 | 0 | – |
| 2007 | 0 | – |
| 2006 | 5 | #17,163 |
Names like Theory
Names given in the same years and the same naming tradition, with a similar sound.
Everly, Oakley, Tilly, Blakely, Ivy, Klarity, Poppy, Harlow, Tinsley, Ensley, Collins, Adley
Names related to Theory
More English names
Lily, Evelyn, Hudson, Harper, Grace, Violet, Willow, Daisy, Riley, Mason, Cooper, Ruby, Hallie, Hazel, Carter, Harrison
Sources
Figures from Popular Baby Names (US Social Security Administration). Nameling last updated them on 20 October 2026. How the figures are worked out, and the data to download.
To cite this page: Nameling, “Theory: name meaning, origin and popularity”, https://www.nameling.co.uk/names/theory, updated 20 October 2026.