Definition of plaid

• n. - A rectangular garment or piece of cloth, usually made of the checkered material called tartan, but sometimes of plain gray, or gray with black stripes. It is worn by both sexes in Scotland.
• n. - Goods of any quality or material of the pattern of a plaid or tartan; a checkered cloth or pattern.
• a. - Having a pattern or colors which resemble a Scotch plaid; checkered or marked with bars or stripes at right angles to one another; as, plaid muslin.