Overview
A tam o' shanter (in the British military often abbreviated to ToS) or "tammie" is a name given to the traditional Scottish bonnet worn by men. The name derives from Tam o' Shanter, the eponymous hero of the 1790 Robert Burns poem.
Description
The tam o' shanter is a flat bonnet, originally made of wool hand-knitted in one piece, stretched on a wooden disc to give the distinctive flat shape, and subsequently felted. The earliest forms of these caps, known as a blue bonnet from their typical colour, were made by bonnet-makers in Scotland. By the year 1599 five bonnet-makers' guilds had formed in cities around the country: Edinburgh, Aberdeen, Perth, Stirling and Glasgow. At the end of the 16th century, it was said that the Scottish caps were the normal fashion of men and servants, and they remained so throughout the 17th century.
Similar in outline to the various types of flat bonnet common in northwestern Europe during the 16th century, the later tam o' shanter is distinguished by the woollen ball or toorie decorating the centre of the crown; the name itself did not enter common usage until the early 19th century, subsequent to the popularity of Burns' poem. The term came to denote a hat, usually associated with Scottish military regiments, derived from the old bonnet, along with the Glengarry and the Balmoral bonnets. The Balmoral was sometimes simply described as synonymous with the tam o' shanter.
From Wikipedia (CC BY-SA 4.0).