Noun
The state of being arborescent; the resemblance to a tree in minerals, or crystallizations, or groups of crystals in that form; as, the arborescence produced by precipitating silver.
Source: Webster's dictionarySome authors restrict the phrase to the case where the edges are all directed towards a particular vertex, or all directed away from a particular vertex (see arborescence ). Source: Internet
When a directed rooted tree has an orientation away from the root, it is called an arborescence, branching, or out-tree; when it has an orientation towards the root, it is called an anti-arborescence or in-tree. Source: Internet