Final answer:
The term 'node' refers to the point on a phylogenetic tree where lineages diverge from the same branch point. This point is crucial in illustrating the evolutionary relationships between species, such as those that define sister taxa and monophyletic groups known as clades.
Step-by-step explanation:
On a phylogenetic tree, the term that refers to lineages that diverged from the same place is node. This branch point indicates where two lineages diverged. A monophyletic group, also known as a clade, consists of a common ancestor and all of its descendants. The root of a phylogenetic tree indicates that an ancestral lineage gave rise to all organisms on the tree, while sister taxa refer to lineages stemming from the same branch point, illustrating a close evolutionary relationship. A polytomy is a branch with more than two lineages, often representing uncertainty in their evolutionary relationships.