What does the moat in stock investment mean?

The moat in stock investment means that listed companies can resist the competition of other companies like a castle with a moat, which means that listed companies have their unique competitive advantages that other companies can't get. Owning a moat will give you a competitive advantage.

A moat, also called a city wall, is defined as a river that people dig around the city wall. In ancient times, it was used for defense. It was excavated in ancient times and surrounded the whole city, palaces, temples and other major buildings. It has a defensive function and can prevent the invasion of enemies or animals.