An underwire bra is a type of women's lingerie designed to provide support and shape to the breasts. It features a thin, semi-rigid wire sewn into the fabric beneath each cup, which helps lift and separate the breasts for a more defined silhouette. Underwire bras come in various styles, including push-up, sports, and lace designs, catering to different preferences and occasions. These bras are popular for their ability to enhance comfort and fit, making them suitable for everyday wear or special events. Proper sizing is essential for effectiveness, as an ill-fitting underwire can cause discomfort. Many women choose underwire bras for their versatility and support.