Where does “Donoghue” come from?

Donoghue (English) comes from Irish Ó Donnchadha, from Irish Ó, from Irish ua, from Old Irish áue, from Primitive Irish ᚐᚃᚔ, from Proto-Celtic awyos, from Proto-Indo-European h₂ewh₂yos — grandfather.

Ancestry of “Donoghue”, step by step

Step	Language	Word	Meaning
1	Irish	Ó Donnchadha	—
2	Irish	Ó	Alternative form of ó used in surnames
3	Irish	ua	Archaic form of ó
4	Old Irish	áue	grandson
5	Primitive Irish	ᚐᚃᚔ	descendant
6	Proto-Celtic	awyos	—
7	Proto-Indo-European	h₂ewh₂yos	grandfather

Every word from Proto-Indo-European h₂ewh₂yos →Every word from Proto-Celtic awyos →Every word from Primitive Irish ᚐᚃᚔ →