Cross is when two things meet at a point, like lines on a piece of paper or roads on a map.
Imagine you're drawing with crayons. If you draw one straight line from left to right, and then another from top to bottom, they cross each other in the middle, just like an X. That spot where they meet is called the point of cross.
Like roads meeting
Think about a city block with streets. One street goes east-west (like your line from left to right), and another goes north-south (like your top-to-bottom line). When those two streets cross, that’s where you can stop and look around, maybe even get ice cream!
Or like fingers meeting
Now, put both hands together in front of you. Your fingers on one hand are going in one direction, and the fingers on the other hand are going in another direction. When your fingers cross each other, they make little X shapes, just like when two lines meet!