CAD is the short name for Computer Aided Design which is computer tool or program using the computer to create designs.
Computer-aided design (CAD) is increasingly being used in t he fashion design industry. Although most designers initially sketch designs by hand, a growing number also translate these hand sketches to the computer. CAD allows designers to view designs of clothing on virtual models and in various colors and shapes, thus saving time by requiring fewer adjustments of prototypes and samples later.
Other /More definition:
CAD is the short name for Computer Assisted Design. CAD is a computer hardware and software systems for designing apparel and implementing their manufacture. (See CAD/CAM)