McCoy and Galloglass are both Anglicisations of terms from what language?
Gallowglass The gallowglasses (also spelt galloglass, gallowglas or galloglas; from Irish: "gall óglaigh" meaning foreign warriors) were a class of elite mercenary warriors who were principally members of the Norse-Gaelic clans of Scotland between the mid 13th century and late 16th century. As Scots, they were Gaels and shared a common background and language with the Irish, but as they had intermarried with the 10th century Norse settlers of western Scotland, the Irish called them "Gall Gaeil" ("foreign Gaels").
Mullaney Mullaney is a surname of Irish origin (from Connacht). It is an Anglicised form of the Gaelic "Ó Maoil Sheanaigh" meaning "descendant of "Maoilsheanaigh"". The Gaelic personal name "Maoilsheanaigh" means "devotee of (Saint) "Seanach"" and the personal name "Seanach" is made up of the element sean meaning "ancient", "old". Many spellings of Connacht named omit the "Sh" and in consequence one theory is that "Mullaney" may be an Anglicisation of "Ó Maoileanaigh" "descendant of "Maoileanach"". The personal name "Maoileanach" means "chief of the marsh". An Ulster family, unrelated to the Connacht family, bore the name "Ó Maoileanaigh".