Cassidy

What Cassidy means

Means “descendant of Caiside”

From the Irish surname, Anglicized from Ó Caiside (“descendant of Caiside”), from cas (“curly-haired”).

Source: Wiktionary, “Cassidy” (revision 89809483), CC BY-SA 4.0. Quoted from the etymology; we don’t write our own.

How popular is Cassidy?

US: Falling: down from #257 in 2015. England & Wales: Falling: down from #686 in 2015.

Biggest US share so far: 1999, when 3,395 girls got the name (#99 that year). First in the US records in 1969.

How common

• About 1 in 2,880 baby girls in the US in 2025
• About 1 in 5,628 baby girls in England and Wales in 2025
• About 1 in 2,982 baby girls in Scotland in 2025

“1 in N” divides by all listed births for that sex. The US list leaves out names given to fewer than 5 babies, and the UK lists leave out names given to 2 or fewer, so the real figure is a little rarer than shown.

Where in the US

Most popular in CO (0.81 per 1,000 girls), PA (0.79 per 1,000 girls), NJ (0.65 per 1,000 girls) in 2025.

SSA state data, 2025. Share of all listed girls born in each state.

US vs UK

Cassidy is #541 in the US and #807 in England & Wales (2025).

Same sex as this page (girls). SSA (US), ONS (England and Wales), NRS (Scotland).

Boy or girl?

In 2025, 91.6% of US babies named Cassidy were girls.

Counts below the publishing threshold (US 5, UK 3) are not included.

How to say it

Wiktionary only lists the US pronunciation so far.

IPA from Wiktionary.

Other spellings parents chose in 2025

• Kassidy240 US · 5 E&W
• Kassidi15 US
• Cassidee6 US
• Cassady5 US

Names that sound the same and differ by a letter or two, with baby counts for the same sex. US and E&W counts.

Nicknames

• Cass
• Cassie

Listed on Wiktionary under “pet forms”.

If you like Cassidy

Girls

• Sydney#348Variant of Sidney, meaning “wide + island”^*
• Bailey#208“outer castle wall”^*
• Mackenzie#228“son, descendant + of Coinneach”^*
• Clare#924“bright, shining, clear”^*
• Hope#352Editor’s note Down from #225 in 2015 to #352 in 2025 in the US
• Madison#40Editor’s note First shows up in US records in 1970, with 5 babies

For a brother

• Chandler#753Editor’s note Used for both: 54% of US babies named Chandler in 2025 were boys
• Grant#228“big, large”^*
• Tanner#475From a surname for “a tanner”^*
• Cameron#76“crooked, bent + nose”^*
• Austin#113“majestic”^*
• Hunter#130From the word “hunter”^*

Picked from the US top 1,000 in 2025: names Wiktionary also files under From a surname, whose US popularity since 1990 rose and fell most like Cassidy’s. Rank is US 2025.