Tam o ' Shanter ( cap ) Tam O ' Shanter ( often abbreviated TOS or Tam ) is a 19th - century nickname for the traditional Scottish bonnet worn by men . It is named after Tam o ' Shanter , the eponymous hero of the poem by Robert Burns . Description . Taking the form of the brimless , bonnet cap that began to be worn throughout northwestern Europe during the 15th century , the ' Tam O ' Shanter ' is usually made of wool and has a " toorie " ( pom - pom ) in the centre . This distinguishes it from other folk bonnets such as the beret , for instance . Although brimless , the TOS has an external hatband which passes around the head ' s circumference , and this , too , distinguishes it from the beret : berets are either band - less where the beret meets the head , or have an internal hatband . Formerly , the Scottish bonnet was made only in blue cloth due to the lack of chemical dyes ( " blue bonnets " ) . , now it is available in a wide variety of colors , as well as tartan . Women have also adopted a form of this hat known as a “ Tammy ” or “ Tam . ” The original form of the Balmoral and the Glengarry in Highland dress , the ' Tam o ' Shanter ' is now best known as the headgear of a number of Scottish infantry regiments and those with Scottish affiliations . Military use . A khaki Balmoral bonnet was introduced in 1915 for wear in the trenches by Scottish infantry serving on the Western Front . This came to be known as the ' Bonnet , Tam o ' Shanter ' later abbreviated to ' ToS . ' Today , the Royal Regiment of Scotland and some regiments of the Canadian Forces continue to wear the ToS as undress and working headgear . The various battalions of the Royal Regiment of Scotland identify themselves by wearing distinctive coloured hackle s on their bonnets . The Black Watch , 3rd Battalion , Royal Regiment of Scotland wear a red hackle in their ToS as do soldiers of The Black Watch of Canada on both their duty ToS and dress balmorals . Some regiments of the Canadian Army wear different coloured toories : the Royal Highland Fusiliers of Canada have traditionally worn dark green ; The North Nova Scotia Highlanders wore red toories during the Second World War ; and the Stormont , Dundas and Glengarry Highlanders wore blue . Most regiments , however , wear a khaki toorie , matching the bonnet . In many Canadian regiments it is traditional for soldiers to wear a ToS , while officers ( and in some cases senior non - commissioned officer s ) wear the Glengarry or the Balmoral . The Tam o ' Shanter was traditionally worn by various regiments of the Australian Army which have a Scottish connection . B ( Scottish ) Company 5th / 6th Battalion , Royal Victoria Regiment wore both a khaki and blue bonnet at various stages . It appears this has now been superseded by the Glengarry . Football kits . In their first season as a football club in 1879 , Doncaster Rovers wore a blue Tam o ' Shanter with a red toorie at the centre as part of their kit . In the UK during World War I , women ' s football teams were formed and some wore knitted Tams . The Tam O Shanter was a main part of the character ` Dr Mactavish ` in the play ` The King Of Spains Treasure ` . This was quite a funny part of the dress .