Reilly

Pronunciation: [ r-EYEL-ee ]

Boy Name #2,800 Most Popular Hidden Gem 2 Syllables

An O'Reilly clan name meaning 'valiant' — Irish pride personified

Irish Irish-American Scottish Australian

Traditional Bold Playful Earthy Strong

Meaning & Origin

"courageous, valiant"

Origin: Irish Gaelic

Language: Irish

"from the Ó Raghallaigh clan"

Origin: Gaelic

Language: Irish

The Story of Reilly

Reilly is an Anglicized form of the Irish surname Ó Raghallaigh, from the clan name Raghallach, which may derive from words meaning 'courageous' or 'valiant.' The O'Reilly clan was one of the most powerful in Ulster, giving the name historical weight in Irish tradition. As both a surname and given name, Reilly (and its common variant Riley) crossed from Ireland to English-speaking countries during and after the waves of Irish emigration in the 19th century.

Reilly gained popularity as a given name alongside Riley in the late 20th century, as Irish surnames became fashionable first names. Riley became a top-10 name in the US, and Reilly remains a favored alternative spelling for those wanting to emphasize Irish heritage through the distinctive 'ei' spelling.

The O'Reilly clan was among the most prominent in Gaelic Ireland, and their name has become a general marker of Irish heritage. The phrase 'the life of Reilly' (meaning a luxurious, easy life) entered English in the early 20th century, giving the name an additional idiomatic association with ease and success.

Fun Facts

The O'Reilly clan ruled Cavan and Meath in medieval Gaelic Ireland
The idiom 'living the life of Riley/Reilly' entered English slang around 1900, meaning a comfortable and easy life
Riley became one of the top 10 names for both boys and girls in the United States in the 2010s

Reilly in Other Languages

Irish Ó Raghallaigh

French Reilly

English O'Reilly

Spanish Reilly

Scottish Reilly

Famous People Named Reilly

Reilly Smith

Athlete

1991

Canadian professional ice hockey player in the NHL

Bill O'Reilly

Entertainer

1949

American television host and political commentator known for The O'Reilly Factor on Fox News

Riley Freeman Fictional

Other

Fictional character on the animated series The Boondocks, voiced by Regina King

Quick Facts

Gender: Boy
Syllables: 2
Popularity Rank: #2,800
Total SSA Count: 46
Cultural Origins: Irish Irish-American Scottish Australian
Pronunciation: Easy
Formality: Casual
Cross-Cultural Ease: High

Common Nicknames

Rei Lee

Pairs Well With

Reilly James Reilly Patrick Reilly Michael Reilly Thomas Reilly Finn Reilly Connor Reilly Joseph

Sibling Names

Declan Siobhan Finn Aoife Liam Bridget Cormac

Also a Girl Name

Reilly is also used as a girl name, ranked #2728.

View Reilly as a girl name →

Similar Names

Wiley Raleigh Wylie Miley Ridley Ripley Raleigh Riley

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Frequently Asked Questions About Reilly

What does the name Reilly mean?

"courageous, valiant" (from Irish Gaelic). "from the Ó Raghallaigh clan" (from Gaelic). Reilly is an Anglicized form of the Irish surname Ó Raghallaigh, from the clan name Raghallach, which may derive from words meaning 'courageous' or 'valiant.' The O'Reilly clan was one of the most powerful in Ulster, giving the name historical weight in Irish tradition. As both a surname and given name, Reilly (and its common variant Riley) crossed from Ireland to English-speaking countries during and after the waves of Irish emigration in the 19th century.

What is the origin of the name Reilly?

Reilly has Irish Gaelic, Gaelic, Irish, Irish-American, Scottish, and Australian origins. In Irish Gaelic, it means "courageous, valiant". In Gaelic, it means "from the Ó Raghallaigh clan".

Is Reilly a boy or girl name?

Reilly is used as both a boy and girl name. As a boy name, it is ranked #2800. As a girl name, it is ranked #2728. Reilly is more commonly used as a girl name.

How do you pronounce Reilly?

Reilly is pronounced r-EYEL-ee.

How popular is the name Reilly?

Reilly is currently ranked #2800 in popularity for boy names in the United States.

What are common nicknames for Reilly?

Common nicknames for Reilly include Rei and Lee.

What are good middle names for Reilly?

Popular middle name pairings include Reilly James, Reilly Patrick, Reilly Michael, Reilly Thomas, Reilly Finn, Reilly Connor, and Reilly Joseph.

What are good sibling names for Reilly?

Names that pair well with Reilly as siblings include Declan, Siobhan, Finn, Aoife, Liam, Bridget, and Cormac.

How many syllables does Reilly have?

Reilly has 2 syllables, making it easy to say and remember.

Is Reilly a common or rare name?

Reilly is an uncommon name, ranked #2800 in the US. Its rarity gives it a distinctive, memorable quality.

About the Name Reilly

Reilly is a boy name with Irish, Irish-American, Scottish, and Australian origins . The name means "courageous, valiant" in Irish Gaelic .

Is Reilly a boy or girl name? Reilly is used as both a boy and girl name. As a boy name, it ranks #2,800 in popularity. As a girl name, it ranks #2,728. Reilly is more commonly used as a girl name.

Reilly is currently ranked #2,800 in popularity for boy names in the United States.

The name Reilly has 2 syllables and is pronounced r-EYEL-ee, making it easy to pronounce and remember.

Common nicknames for Reilly include Rei and Lee. These shorter forms provide casual alternatives while keeping the elegance of the full name.