Cassidy

About Cassidy

Cassidy is an Irish surname that became a given name for both girls and boys. Its roots lead to a byname meaning “curly-haired.” Pronounced KAS-ih-dee, it has three syllables and the familiar short forms Cass, Cassie, and Cassy.

An Irish surname becomes a given name

The surname is an English form of Irish Ó Caiside, built from the personal byname Caiside. Caiside comes from cas, meaning “curly” or “twisted,” and referred to curly hair. This gives Cassidy a specific descriptive origin behind its modern surname style.

As a given name, Cassidy was very uncommon before the 1970s. It established itself during the 1980s and rose much more sharply during the 1990s. That comparatively recent American popularity sits alongside the older Irish surname history.

Kassidy is a spelling variant. Cass and Cassie shorten its opening syllable.

Butch Cassidy and western history

The outlaw known as Butch Cassidy was born Robert LeRoy Parker. Cassidy was part of an adopted public name, and he became a leader of the loosely organized Wild Bunch.

The gang used refuges across the American West, including Wyoming’s Hole-in-the-Wall country. Train robberies at Wilcox in 1899 and Tipton in 1900 became part of its notoriety. Cassidy’s personal presence at those crimes is not firmly established, even though they are closely connected with his gang’s story.

His later life also attracted conflicting accounts. Stories of his death in South America and claims that he returned to the United States have contributed to the surrounding legend. The 1969 film Butch Cassidy and the Sundance Kid helped carry that legend to later audiences.

The name consequently has a western screen association as well as an Irish surname origin. The outlaw’s adopted surname is a different kind of use from a modern child receiving Cassidy as a first name.

Cassidy Freeman on television

Actor Cassidy Freeman gives the name a contemporary first-name connection. In The Righteous Gemstones, she plays Amber Gemstone, Jesse’s wife and a mother of three.

Amber belongs to the series’ central family world, presenting herself as a supportive spouse while also speaking her mind. Freeman’s role puts Cassidy into television comedy and contrasts with the much older western association carried by Butch Cassidy. Here the name appears in the performer’s own name, rather than as the name of the character.

American popularity

Cassidy’s strongest year for American girls was 1999, with 3,395 births and a rank of #99. In 2025 it ranked #541, with 558 girls.

For boys, its strongest year was 1984, when 169 received the name and it ranked #665. There were 51 boys named Cassidy in 2025. These separate trends show how the spelling became substantially more common for girls while continuing to appear for both sexes.

How popular is Cassidy?

In 2025, Cassidy ranked #541 among girls in the United States, with 558 recorded uses. The U.S. birth records first list this spelling for girls in 1969; its largest annual count was 3,395 in 1999. Rankings count each spelling separately. They describe national use, so local familiarity can differ. The popularity chart shows whether the name has remained common, returned after a quieter period, or risen recently.