The answer you may be looking for is 'Trews' although I think it worth mentioning that you will find it very, very hard to find any normal member of the public in either Scotland, Northern Ireland or the Republic of Ireland ever wearing these. If anything we would be wearing a kilt and even this is not usually worn unless at a special occasion (like a wedding), an event that requires formal dress or a ceremony of some sort. Tartan trousers and the like are sold to tourists in many tourist shops especially in Edinburgh but these are made specifically for this purpose. I have lived in Scotland all my life and the only people I have ever seen wearing tartan trousers are the tour guides at Historic Scotland attractions.
Tartan trousers worn in Scotland are called trews.
Trews. I don't think that they are worn in Ireland.
Pajamas are clothes for wearing to bed and sleeping in, usually a loose-fitting shirt and trousers.
Usually, surnames with the "Mc" or "Mac" prefix come from either Ireland or Scotland.
The United Kingdom. The United Kingdom of Great Britain and Northern Ireland usually abbreviated to just UK.
Patterson or Paterson is usually associated with Scotland. However since it means son of Patrick a popular name in Scotland Ireland and England in medieval times it can be found in all three places. It's spread to Ireland was mainly however from the Lowlands of Scotland into Ulster and outwards from there.
The United Kingdom of Great Britain includes Northern Ireland, England, Scotland and Wales, Great Britain is surrounded by over 1000 smaller isles which are included in the United Kingdom
Freddy usually wears brown trousers.
Only three regions make up Great Britain. They are England, Scotland & Wales. The United Kingdom is made up of four regions ; England, Scotland, Wales & Northern Ireland. Within the UK, these regions are usually called countries.
Usually yes. Take the United Kingdom for example - the UK encompasses the countries of England, Scotland, Wales and Northern Ireland.
The United Kingdom of Great Britain and Northern Ireland (which comprises England, Scotland, Wales, Northern Ireland) and the Republic of Ireland are the countries in the British Isles. Only the UK and the Republic of Ireland are countries in the sense of being members of the United Nations.
the bagpipes are usually associated with Scotland