Shortening is a semisolid fat used in food preparation, especially baked goods, and is so called because it promotes a "short" or crumbly texture (as in shortbread). Shortening is fat or lard from an animal or vegetable. The term "shortening" can be used more broadly to apply to any fat that is used for baking and which is solid at room temperature, such as butter, lard, or margarine. Shortening often has a higher smoke point than butter and margarine, and it has 100% fat content, compared to about 80% for butter and margarine.
Although the term has been in use for many years, it is now known that shortening works by inhibiting the formation of long protein (gluten) strands in wheat-based doughs. The similarity in terms is entirely coincidental since full understanding of the structure and chemistry of dough is comparatively recent.