Ó Troighthigh is a Gaelic-Irish surname.
Overview
The Ui Troighthigh (foot-soldier) were natives of Corcomroe. The earliest mention of the family occurs in 1003, when
1003. The slaying of Conchobar son of Mael Sechnaill, king of Corcu Modruad, and of Amlaíb, son of Lochlainn, and of Aicher Ua Traigthech in the west of Connachta; and Cathal, son of Labraid, was killed by the sons of Donnchadh Finn. The slaying of Conchobar son of Mael Sechnaill, king of Corcu Modruad, and of Amlaíb, son of Lochlainn, and of Aicher Ua Traigthech in the west of Connachta; and Cathal, son of Labraid, was killed by the sons of Donnchadh Finn.
The Ui Troighthigh became a hereditary medical family, with branches in what is now County Clare, County Limerick and County Tipperary, as well as elsewhere in Munster, and Leinster.
The name is now anglicised as Troy. Members of the Anglo-Irish de Treo family (associated with Limerick city since 1189) and the Gaelic-Irish Ó Tréamháin family also use the form Troy, making members of all three unrelated families indistinguishable.