A tartan skirt is a kilt, which is only 4 letters, but the Irish kerns (Gaelic soldiers) wore a leine, which was really a long shirt but is often (incorrectly) depicted as a kilt.
The kilt or kilts.
You're thinking of the kilt
A kilt.
Kilt
A tartan skirt is a "kilt." Perhaps your answer is plural.
a Kilt.
Since the 19th century, the kilt has become associated with the wider Scottish and Gaelic cultures. Kilts are often made of a woolen cloth in a tartan pattern. Usually worn at formal events, competitors also wear this Scottish outfit at the Highland Games.
James Tartan's birth name is James Richard Tartan.
The correct name for a Scottish tartan skirt is a "kilt." Traditionally worn by men, kilts are made of tartan fabric, which features a specific pattern of crisscrossed horizontal and vertical bands in multiple colors. Women may also wear kilts or variations of them, often referred to as "kilted skirts." These garments are an important part of Scottish heritage and culture.
none... tartan is scottish.
It is known around the world as a skirt.
I have never heard it called anything else in Scotland, but in the US they call is plaid.