1. a point in a graph, tree diagram, or the like at which lines intersect or branch.

2. a single point or unit in an associative model of memory. Nodes typically represent a single concept or feature, are connected to other nodes (usually representing semantically related concepts and features) by links in an associative network, and may be activated or inhibited to varying degrees depending on the conditions.

3. in artificial intelligence, see neural network. —nodal adj.