The name itself is of Gaelic origin, but is a source of some debate.

Sometimes folk etymology has totally obscured the Gaelic origins of a name.

Irish kinship is limited to a small number of words of Gaelic origin used in identifying relatives.

Niall is a male given name of Gaelic origin, thought to mean "champion".

There could be several possible Gaelic origins for this name, with bheathain (lively one) being the most likely.

Which Gaelic origin of the name may depend, to some extent, on geographical location.

The word itself is of Gaelic origins and means "great sword".

One source, however, claims that the term is of Scottish Gaelic origin.

The place name elements you list are good indicators of a Gaelic origin for a name.

Neil is a masculine given name of Gaelic origin.