What is the difference between Plaid and Tartan?

Plaid Definition

Plaid is often mistakenly used in place of Tartan (particularly in North America), but in Scotland, a plaid is a large piece of tartan cloth, worn as a type of kilt or large shawl The term plaid is also used in Scotland for an ordinary blanket such as one would have on a bed.

Plaid refers to the clothing, no matter what the pattern of the fabric is. Tartan is the pattern.

Plaid in USA vs Scotland

While plaid is the North American word for tartan in Scotland, people would only use the word plaid if referring to the length of tartan that a piper wears over his shoulder when in formal dress.

Tartan Definition

Tartan (Scottish or Gaelic language: breacan [ˈpɾʲɛxkən]) is a patterned cloth consisting of criss-crossed, horizontal and vertical bands in multiple colours. Tartans originated in woven wool, but now they are made in many other materials, and the term is also used for the type of pattern itself. Tartan is particularly associated with Scotland.  Scottish kilts almost always have tartan patterns.

Tartan is made with alternating bands of coloured (pre-dyed) threads woven as both warp and weft and at right angles to each other. The weft is woven in a simple twill two over—two under the warp, advancing one thread at each pass. This forms visible diagonal lines where different colours cross, which give the appearance of new colours blended from the original ones. The resulting blocks of colour repeat vertically and horizontally in a distinctive pattern of squares and lines known as a sett.

Patterns for Surnames and Places

The patterns were simply different regional checked-cloth patterns, chosen by the wearer’s preference—in the same way as people nowadays choose what colours and patterns they like in their clothing, without particular reference to propriety. It was not until the mid-nineteenth century that many patterns were created and artificially associated with Scottish clans, families, or institutions who were (or wished to be seen as) associated in some way with a Scottish heritage. Tartan is registered to surnames but there are also have tartans named after places.

Plaid vs Tartan vs Check in Summary

So in short:

• A check is a pattern of modified stripes consisting of crossed horizontal and vertical lines forming squares.
• Tartan is a pattern consisting of criss-crossed horizontal and vertical bands in multiple colours.
• Plaid is a cloth made with a tartan pattern wrapped around the waist and cast over the shoulder and fastened at the front.