Neil

Neil is a masculine given name of Gaelic origin. The name is an Anglicisation of the Irish Niall which is of disputed derivation. The Irish name may be derived from words meaning "cloud", "passionate", or "champion". As a surname, Neil is traced back to Niall of the Nine Hostages who was an Irish king and eponymous ancestor of the Uí Néill and MacNeil kindred. Most authorities cite the meaning of Neil in the context of a surname as meaning champion.

The Gaelic name was adopted by the Vikings and taken to Iceland as Njáll (see Nigel). From Iceland it went via Norway, Denmark, and Normandy to England. It was first mistakenly being translated into Latin as Nigellus from Niger, meaning black. The name also entered Northern England and Yorkshire directly from Ireland, and from Norwegian settlers. Neal or Neall is the Middle English form of Nigel.

As a first name, during the Middle Ages, the Gaelic name was popular in Ireland and Scotland. During the 20th century Neil began to be used in England and North America, and grew in popularity throughout the English-speaking world; however, in England, it has recently been eclipsed by the Gaelic form.

The surname Neil is a reduced form of the surname McNeil (from the Gaelic Mac Néill, "son of Niall"), or variant form the surname of Neill (from the Irish Ó Néill or the Scottish Gaelic Mac Néill, meaning "descendant of Niall" and "son of Niall".

The name passed from Ireland to Scotland where it had the Mc/Mac prefix. Some Scottish McNeill's returned to Ireland in the 14th century and are associated with MacNeill, MacGreal, MacReill, and Mag Reil surnames.

The Manx version of the name is Kneal (1598), Kneale (1655), or Kneel (1636). It evolved from McNelle (1408) and MacNeyll (1430) becoming Kneal by 1598.

Variants of the given name include: Neale and Neal.

The table below sets out the various surnames derived from Niall

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Wikipedia