If that is the correct spelling, it is not Gaelic.
In Scottish Gaelic it is spelled Mòrag.
MacÌosaig
Easáias (from the Irish Bible); Isaiah in Scottish Gaelic.
The Irish language 'equivalent' of the Scottish Ian could be either Seán or Eoin, (forms of John). The original Scottish Gaelic spelling of Ian is Iain, incidentally.
In Scots Gaelic MacAulay is MacAmhlaigh; 'the MacAulays' however is Clann 'IcAmhlaigh.
John an ghleanna / Seán an ghleanna
duine as Óileáin Sgitheanach / Albanach
The correct spelling is Gaelic (Scottish or Irish dialects).
The spelling doesn't appear to be correct.
Irish (Gaelic): Éirinn go brách (aer'-rin guh brawch) Scottish Gaelic: ...
In Irish it's "Uilliam" In Scottish Gaelic: Uilleam; Liam is more common in Irish.