# Moriarty (surname)

Source: https://namelineage.com/surname/moriarty/  
Publisher: Name Lineage. Counts from the US Census Bureau; origin and etymology from Wiktionary; bearers from Wikidata. Data updated 2026-11-11.

A surname from Irish.

| Field | Value |
|---|---|
| Origin | Irish |
| Type | patronymic, formed from a father’s (or ancestor’s) given name |
| People in the US (2010 Census) | 10,005 |
| US rank (2010) | 3,564 of 162,253 |
| How often | about 1 in every 30,859 people |
| Change since 2000 | +3.6% (9,661 in 2000) |
| Pronunciation | /ˈmɔːɹiɑː(ɹ)ti/, 4 syllables |
| Variant spellings | none recorded |

## Etymology

From Irish Ó Muircheartaigh (“descendant of Muircheartach”), a name from muir (“sea”) + ceardaí (“craftsman”).

## Who carries it

Share of people named Moriarty in the 2010 US Census by the Census's own race and ethnicity groups. The Census suppresses a share when the count behind it is small.

| Group | Share |
|---|---|
| White (not Hispanic) | 96% |
| Black (not Hispanic) | 0.4% |
| Hispanic or Latino (any race) | 1.9% |
| Asian and Pacific Islander | 0.6% |
| American Indian and Alaska Native | 0.2% |
| Two or more races | 1.1% |

## Where

Wikidata records people named Moriarty in the United States and Australia.

## People named Moriarty

- Erin Moriarty, American actress
- Cathy Moriarty, actress
- Michael Moriarty, American-Canadian actor and musician (b. 1941)
- Liane Moriarty, Australian author
- Brian Moriarty, American video game developer
- James Moriarty, Australian track cyclist
- Jaclyn Moriarty, Australian writer

## Similar surnames

Moriarity.

## How to read these numbers

A Census count is people alive and counted in 2010, not births, and names occurring fewer than 100 times are not published at all. Ethnicity shares are the Census's own categories.