1. A tree-like diagram (dendrogram) illustrating the evolutionary descent of any group of organisms.
2. An evolutionary tree diagram with groups arranged by branch points to show their relative relationships.

Groups that are closer together share a more recent common ancestor than those which are farther apart.

3. A diagram, resulting from a cladistic analysis, which depicts a hypothetical branching sequence of lineages leading to the taxa (category of organisms) under consideration.

The points of branching within a cladogram are called nodes. All taxa occur at the endpoints of the cladogram.