Dungan
An Irish surname usually explained as a shortened form of Dungannon, the place-name meaning a stronghold name in Ulster.
The #8,611 most common surname in the United States (2010 Census) — about 1 in every 80,845 Americans shares it.
Etymology
This surname is generally taken as a shortened form of the Irish place-name Dungannon. The place-name is built from dun, meaning 'fort' or 'stronghold,' and is often explained through an older Gaelic compound referring to a fortified place. The historical sources you provided treat Dungan as a contraction of that place-name rather than as a separate word or occupation name.
History
The name appears in Irish genealogical and surname discussions as an established family name, especially in Ulster-related contexts. The Matheson material shows Dungan clustered among Irish surnames, while later American usage reflects broader migration from Ireland. Because the old sources are brief and partly indirect, the exact derivation should be treated as traditional rather than certain in every detail.
Origin
Regions
Variant spellings
Fun fact
One nineteenth-century source glossed the underlying place-name as a 'stronghold,' showing how often Irish surnames were linked to local fortifications or territories.
From the historical record
“•QoTTOijn, Dondon, Dundon. "OonsATi, Dongan, Dungan, Dun- can. "DonTTOtin, Dondon, Dundon. "OjiAC, Drake.”
— Sloinnte Gaedheal is Gall: Irish names and surnames