MacAonghais is the Scottish Gaelic form of the surname MacInnes. This patronymic surname literally means "son of Aonghas" (anglicized as Angus). The name itself is rooted in the personal name Aonghas, which is the Scottish Gaelic version of the Old Irish Aonghus.EtymologyThe name traces back to the Old Irish Óengus, a compound of óen "one" and guss "force, strength," thus interpreted as "one strength." In Irish mythology, Aonghus (often called Mac Óg, meaning "young son") was a god of love and youth, belonging to the Tuatha Dé Danann, the supernatural race in Irish lore. He was the son of the Dagda and Boann. The name was also borne by an 8th-century Pictish king, several Irish kings, and a few saints, including a 9th-century bishop of Tallaght.Origin and HistoryThe surname MacAonghais originated in the Scottish Highlands as a patronymic, indicating descent from one named Aonghas. As Scottish Gaelic names were anglicized, MacAonghais gave rise to a wide array of English-language variations. The Wiktionary record notes many descendants: Guinness, McInnes, McInnis, McGinnis, McGuinness, Maginnis, among others. The surname also appears as MacAngus and Innes (through truncation). In Irish Gaelic, the equivalent is Mag Aonghuis; both forms show how the root name Aonghas has been adapted across Gaelic-speaking regions.Notable Bearers and DistributionWhile the Gaelic original is rare outside of Scotland, its English forms (such as Guinness, Heaney) are widely known. Guinness, famously the name of the Irish brewing dynasty (the Arthur Guinness family), derives directly from MacAonghais. Other surnames like Hennessy also stem from the same root (Mac Aonghusa in Irish).Meaning: "Son of Aonghas" (Aonghus)Origin: Scottish GaelicType: Patronymic SurnameUsage Regions: Scotland, Irish diaspora, English-speaking world via derivatives