What does CAD mean when creating a game engine?

Question

C++ / C#

Can someone explain in simple terms with an example what is CAD (CAD) when creating a game engine?
It’s just that I didn’t understand much from these words - Computer-aided design system - an automated system that implements information technology for performing design functions [1], is an organizational and technical system designed to automate the design process, consisting of personnel and a set of hardware, software and other tools automation of its activities[2][3]. Also, the abbreviation CAD is widely used to refer to such systems.