"MacOmish" is one of the main Sept Names of Clan
MacThomas.
The name MacOmish is a variation of McComie, the name used by the 5th, 6th and 7th Chiefs
and their families. Some descendants still using McComie, at the time of the break up of the Clan,
moved elsewhere in Scotland and adopted slight spelling variations. At the end of the 17th century,
some people with these names are recorded as living in Inverness-shire, further north, in Aberdeenshire and in the Crieff area of Perthshire.
Around the same time, there are also records of a few people with these names in the south-west
of Scotland and in Northern Ireland. Whilst we have no way of knowing for certain, it seems that this
group may be descendants of an earlier migration of MacThomases to the south-west of Scotland,
who became known as McColms.
Some seem to have travelled the short distance over the sea to Northern Ireland where they
were usually called McComb. In much the same way as above, it is not difficult to see how some
of those who settled in Galloway and later set sail for Ireland may have become MacOmish.