High Quality Content by WIKIPEDIA articles! The waistline is the line of demarcation between the upper and lower portions of a garment, which notionally corresponds to the natural waist but may vary with fashion from just below the bust to below the hips. The waistline of a garment is often used to accentuate different features. The waistline is also important as a boundary at which shaping darts (such as those over the bust and in the back) can be ended.Similar to necklines, waistlines may be grouped by their shape, depth, and location of the body.