In the past, people looked at weather and related it to something in their lives. For instance, cloud types are often described by their shapes in the sky. The mareâs tails are wispy cirrus clouds while the mackerel scales are small clumpy altocumulus clouds resembling fish scales in the sky. In the days of large sailing ships, this meant a storm would be approaching soon and the sails should be lowered to protect from the accompanying high winds.
For me, the best way to remember the difference is that a shift dress actually shifts - with the bottom having a wider skirt than the top; meanwhile, a sheath dress is narrower, with pretty much identical measurements at the bust and the knees. Here is a visual tool to help illustrate the difference:
The sheath is a long, narrow, slim-fitting silhouette with straight, lines. A sheath dress is usually made from lighter fabrics, such as satin or chiffon, which is more suitable for the body-skimming shape of the sheath silhouette.