A node is a point of connection. Technically, a traffic intersection is a node since multiple roads connect at that point.
Another type of node is a round swelling. Some are abnormal, like a node you discover on your knee, but others, such as a lymph node, are a normal part of your immune system. You can also find a node on a plant: it’s the swelling on the stem marking the spot where leaves emerge. Computer techs know that a node can also be a piece of equipment — like your cable modem — in a computer network. In a sense, that kind of node is also a connecting point — like the traffic intersection.