MallowbyNames

Theta

THAY-tuh · The eighth letter of the Greek alphabet, used as a name.

Peak popularity
1907
Usually for
Girls
Trend
Holding steady

Holding steady.

Popularity of Theta since 1907

Babies named Theta per year in U.S. Social Security records.

71320192019602000Most births 1907Girls
Data table (by decade)
DecadeGirls
1900s33
1910s56
1920s101
1930s84
1940s62
1950s40
1960s21
1970s0
1980s0
1990s0
2000s0
2010s5
2020s0

Meaning & origin

Theta is an exceedingly rare name that first appeared in U.S. birth records in 1907, though it has never achieved widespread use. Its peak year remains 1907, when it first entered the records, but it has never charted in the top 1,000. The name has remained consistently rare, with a stable trajectory showing no significant increases or decreases. Theta follows a long tradition of using Greek letters as names, a practice that gained some popularity in the early 20th century. Today, it is a true rarity, likely chosen by parents seeking a distinctive and scholarly name.

Theta (Θ, θ) is the eighth letter of the Greek alphabet, derived from the Phoenician letter teth. Its use as a personal name is rare and likely stems from the tradition of naming children after letters, a practice found in various cultures. In English-speaking countries, it has occasionally been used as a given name since the early 20th century.

Sibling names for Theta

Names that share Theta's style, for a brother or sister.

Sisters: Alpha, Gamma, Delta, Epsilon, Zeta

Brothers: Kappa, Lambda, Sigma, Omega, Pi

A parent animal hugging its little one, the personalized name page

T is for Theta, our favorite little girl.

T is for Theta…”

In a Mallowby alphabet book, Theta's letter becomes Theta's page: hand-illustrated, printed hardcover or paperback, made just for them.

Make Theta's book

Books for siblings or grandkids? The second book is 15% off.

Questions parents ask

What does the name Theta mean?
Theta is the eighth letter of the Greek alphabet, with no additional inherent meaning beyond its alphabetic role.
Is Theta a popular baby name?
Theta is extremely rare. It was first recorded in 1907, but it has never ranked among the top 1,000 names in the United States. In 2025, its popularity remains negligible.
Is Theta a boy's or girl's name?
Theta is typically used for girls, though its rarity makes it unisex in practice.