Thankfully local genealogist and historian Brian Mitchell has the answer having sorted the Dohertys from the McLaughlins, and the Gallaghers from the Kellys, in his book ‘The Top 300 Surnames of Derry-Londonderry’, published by Clearfield in Baltimore in the United States.
The book is based on the 1989 Foyle Community Directory, which lists 1,860 unique surnames in Derry City.
Brian looked at the number of entries and ranked the surnames in order of mentions. Where is yours in the list?

25. 16. Hegarty.
16. Hegarty. Irish: Originating in south Derry this sept can trace its descent from Eoghan, son of the 5th century High King of Ireland, Niall of the Nine Hostages. By the 17th century they had established themselves in Inishowen, County Donegal, and in County Derry, west of the River Roe. The Hegartys were sub-lords to the O'Neills (Brian Mitchell). Hegarty ranks 16th on the list with 72 mentions. Pictured is the late Maureen Hegarty, a celebrated singer, with trophies won at Feis Doire Colmcille in 1966. Photo: Journal archive

26. 14. Hamilton.
14. Hamilton. Scottish: Derived from the Yorkshire place name of Hambleton, meaning crooked hill, this surname was introduced to Scotland in the 13th century by a Norman family from Leicestershire. In the 14th century the Hamiltons were granted the lands of Cadzow in Lanarkshire by Robert the Bruce. Hamilton is a name very much associated with the Scottish 'undertakers' or landowners who were granted large estates in County Armagh, Fermanagh and Tyrone at the time of the 17th century Plantation of Ulster (Brian Mitchell). Hamilton ranks 14th in the list with 89 mentions. Pictured is former Thornhill College principal Marguerite Hamilton with former Thornhill College A Level students Emer McCarron and Anna McAree in 2017. Photo: Archive

27. 13. O'Donnell.
13. O'Donnell. Irish: Taking their name from Domhnall, who died in 901, and tracing their descent from Conal Gulban, son of the 5th century High King of Ireland, Niall of the Nine Hostages, this sept, from their base around Kilmacrenan, County Donegal, rose in importance from the 13th century to the position of overlords of Donegal. The O'Donnells, alongside the O'Neills, led the Ulster Rebellion of 1594-1603 against English encroachment (Brian Mitchell). O'Donnell ranks 13th on the list with 91 entries. Pictured is Derry Girls star Jamie-Lee O'Donnell. Photo: James Flood

28. 12. Brown.
12. Brown. English and Lowland Scottish: Derived in most cases as a nickname for someone who was 'brown-haired' or 'brown-skinned'. An Anglo-Norman family of this name settled in Ireland in the 12th century. Scots-Gaelic: At least two septs, one meaning son of the judge and the other meaning son of the brown lad, had their names anglicised to Brown. On their outlawing by the Crown in the 17th century one of the names adopted by members of Clan Lamont was Brown (Brian Mitchell). Brown ranks 12th on the list with 91 mentions. Pictured is Marie Brown of Foyle Women's Aid. Photo: Archive

