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A [[tree]] with a distinguished vertex, the ''root''.  A rooted tree has a natural [[Graph, oriented|orientation]] in which all paths are directed away from the root: such an oriented tree is an ''[[arborescence]]''.

A ''rooted plane tree'' is one with a prescribed cyclic order of the edges incident with each vertex.

[[File:Rooted tree 230000.svg|center|200px|An example of rooted tree]]

Rooted trees play a central in [[Butcher series]] and the algebraic notion of [[pre-Lie algebra]].

[[Category:Graph theory]]