Imagine you are playing a game with your friends where you need to protect something valuable. You will need to create a wall of people to keep the valuable thing safe. This is called a defensive wall.
A defensive wall is a group of people or things that are lined up together to protect something. Just like how you make a wall with your friends to protect your valuable, a defensive wall is used to protect a town or a castle, or even a team in a sports game.
The people on the defensive wall will work together to stop anything from getting past them. They will use their strength and skills to keep the enemy away. Sometimes they will even build a wall out of rocks and other materials to make it even harder for the enemy to break through.
The defensive wall is an important defense tactic in many situations. It helps to keep things safe and protected from harm. Just like how you protect your valuable with a wall of friends, people and things in real life can be protected with a defensive wall.