Sheath

A sheath tracks the body along its full length and usually ends at or just above the knee. Darts, the small stitched folds that curve flat fabric over the bust and waist, do the shaping. Cut in a stretch knit and pulled tighter, the same idea sells as bodycon; extended straight to the ankle it becomes a column.

Tailoring supplies the convention behind it: a sheath is judged like a suit, on clean lines and an absence of pulling. Every horizontal crease is a report on fit, which is why the silhouette dominates workwear, where a smooth vertical line signals precision. Lining and fabric weight do most of the work. A lined sheath in a dense double knit around 250 grams per square meter holds its shape through eight seated hours. By contrast, a thin single knit prints every seam underneath.

Low fit tolerance is the price. The dress measures you at bust, waist, hip and thigh at once, so one dimension off means alteration. Stride is limited by hem width. A back vent, the short open pleat at the center hem, exists to give the stride back. Try stairs in the fitting room, not just the mirror.

Set it against an A-line before you commit. Both start fitted through the bodice, but the A-line releases at the waist. A sheath keeps measuring you all the way to the hem, so it reports the half inch an A-line hides. Pinch the fabric at your hip: if you cannot lift a quarter inch clear of the skin, it will crease there by noon. Wear shows first at the seat, where hours of sitting stretch the weave into a shine or a bagged patch.