Cassidy
/ˈkæs.ɪ.di/
Cassidy is an anglicised form of the Irish surname Ó Caiside, derived from the byname Caisid, which is thought to mean “curly-haired.” The name entered American use through the 1970s-1980s trend for Irish and Western-flavoured surnames.
The outlaw Butch Cassidy (1866-1908) kept the name familiar in American culture, and the 1969 film Butch Cassidy and the Sundance Kid reinforced its Western associations just before the name began its rise as a given name in the 1980s.
Cassidy peaked at No. 99 in 1999 with 3,395 births. In 2024 it ranks No. 476 with 646 births, a classic 1990s name now in a gradual decline.
What the name Cassidy means
Country singer Cassidy Pope (now Caitlin Rose) and rapper Cassidy (born Barry Adrian Reese, 1982-) represent two very different public bearers, showing the name’s breadth across demographics.
Three syllables — KAS-ih-dee — with stress on the first beat. The name has an energetic, slightly country-Western quality that feels both modern and rooted.
Parents who chose Cassidy in the late 1990s often wanted an Irish surname name with a feminine -y ending that felt fresh at the time without being invented.
Variants include Kassidy and Kasidy, both of which appeared in SSA data after Cassidy established the sound. The original Irish spelling remains the standard form.
US popularity over time
Numerology and symbolism
Based on Pythagorean numerology — a traditional system linking name letters to numbers. Presented for cultural interest.
Famous people named Cassidy
Cassidy - similar names
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