Reilly

Reilly comes from the Irish clan name Ó Raghallaigh, so the name carries the straightforward sense of being a descendant of an ancestor called Raghallach. In practice, Reilly feels less like a literal descriptor and more like a nod to Irish family history and clan identity.

As a given name, Reilly has a lively, approachable tone. It feels modern and unpretentious while still retaining a hint of old-world roots. The name sits comfortably between playful and refined, and it can work equally well for a child who will be sporty, creative, or quietly steady. If you are choosing between related options, names such as Riley appear alongside Reilly in contemporary use, each carrying a slightly different spelling personality.

The name Reilly originates in Ireland as the anglicised form of the Gaelic Ó Raghallaigh, a family name belonging to several distinct clans across Irish history. The original Gaelic personal name Raghallach is old and its precise meaning is not certain, so the most reliable historical description is that Reilly signified membership of a particular family or sept. Over centuries the surname became widespread and influential, especially in counties such as Cavan and Longford.

As surnames became usable as first names in English-speaking countries, Reilly followed the broader trend of adopting family names as given names. This happened most readily in places with Irish immigrant communities, including the United Kingdom and the United States. The spelling Reilly preserves the traditional surname look, while variants such as Riley grew in popularity as given names. Today Reilly is used as a first name, often by parents who want a contemporary, gender-neutral choice with clear Irish roots. When discussing original forms it is common to see the Gaelic Ó Raghallaigh or the anglicised O'Reilly, both of which point back to the same clan identity.