Re:  Mac Dhonnchaidh, Son of Donnchadh, variously anglicized as MacConochie, Conachie, McConkey, etc.   Is fíor do Mhac Giolla Iasacht, cinnte, ach … / MacLysaght is correct,  of course.  However, as pointed out by Robert Bell in his THE BOOK OF ULSTER SURNAMES on p. 54:  “There were also MacConochie septs of Clan Campbell, one of which, the MacConachies of Inverawe in Argyleshire, descend from the 14th century Duncan or Donachie Campbell of Lochow.  The Clan Gregor MacConachies descend from the three sons of Duncan, 17th chief of MacGregor, by his second wife.  There was also an old sept of MacConachies on the island of Bute.  In Ulster all this becomes very complicated.  As has already been stated, Donaghy is also an Irish name.  Duncan, though a Scottish name used as an anglicization of Donachie and MacConachie, has also in Ulster been used for the Irish Donoghue as well as Donegan and Dinkin.  Besides MacDonagh (Mac Donnchadha), Donaghy has also been used for Donohoe.  MacConaghy has been noted as a synonym of Conaty, MacConaughty, MacConnerty, and even Quinn.”   As noted on the R-M222 list some time back, most of these anglicizations are phantom surnames.  The actual, underlying surname for MacConochie et. al. is Mac Dhonnchaidh which, in turn, is a late medieval grammatical development of the earlier genitive form Mac Donnchadha.  Donnchadh is usually translated as Dark Warrior.  Donnchadha and Donnchaidh and Dhonnchaidh = of Dark Warrior.  Mac Donnchadha and Mac Donnchaidh and Mac Dhonnchaidh = Son of Dark Warrior.   Go raibh sé sin cabhrach  /  Hope that’s helpful, Gearóid / Jerry