English from Old German "heart", "mind" or "spirit"; introduced into Britain by the Normans. Sometimes Hugh and Hugo (the English, Dutch and German form of Hugh) can be used synonymously.
In the west Highlands of Scotland Hugh is the accepted English equivalent of Eòghan; elsewhere Hugh is the Anglicized form of Aodh and of Ùisdean.
In most parts of Scotland Shug and Shuggie are generic nicknames for Hugh.
One correspondent [J-AC] records a family over several generations using Hugh, Hew and Ewen interchangeably in Argyll, Scotland.
According to the Clan MacLean Website, Hùisdean or Ùisdean is the Gaelic equivalent of Hugh, Ewen and Austin and a correspondent [AC2] confirms that Hugh and Austin are used as synonyms in Scotland.
Huchin, a medieval diminutive for Hugh, has given rise to the surnames Hutchin and Hutcheon, from which the given name Hutcheon was derived in the 17th century [SW].
Hugo was the form used in early documents in Latin, with appropriate case endings. The form Hugonis is the possessive case = "of Hugh".
A corrspondent [EK2] has recorded Hugh used as a pet name for a family member whose given name was Hubert.