O'Leahy Last Name: Meaning and Heraldic Roots

O'Leahy sits within the Leahy family of names, which has Irish roots. Name scholars give the meaning as “Descendant of Laochdha ("heroic")”.

Spelling and variants

O'Leahy simply joins the particle O' to Leahy, a habit common in Irish naming. Census takers and immigration officers often wrote what they heard. You may also find the name written Lahey and Leahey.

Heraldry and the O'Leahy name

Looking for a O'Leahy coat of arms? Arms were granted to families, not to surnames, and our research shows which heraldic tradition fits yours.

For the full story, order the O'Leahy surname pack.