A plaid shirt is a type of clothing item that features a pattern of alternating horizontal stripes, known as a plaid design. The term can also refer to any garment made from fabric with this distinctive pattern. Plaid shirts are typically associated with casual or outdoor wear and come in various styles such as button-down, crewneck, or V-neck. They are often worn as part of a casual or preppy style, but can also be dressed up for more formal occasions.