Nyhan

Nyhan is a surname of Irish origin. It is an anglicized form of the Gaelic Ó Nialláin, meaning "descendant of Niallán". The personal name Niallán is a diminutive of Niall, a popular Irish given name. The surname is most common in the province of Ulster in Ireland, particularly in counties Tyrone and Armagh.

Notable individuals with the surname Nyhan include the American physician and biochemist W. Allen Nyhan, known for his work in medical genetics and the development of treatments for inherited metabolic disorders. There are also historical figures and families associated with the name in Ireland. The distribution of the Nyhan surname reflects historical settlement patterns and migration within Ireland and to other parts of the world, such as the United States and Australia. The name continues to be carried by people of Irish descent globally.