Is there a term to describe all non-root nodes in a tree?

Root covers the root, wha开发者_运维知识库t are the rest of the nodes collectively called?

Just like in the real world: branches and leaves

They are all child nodes (of the root or some other node).

I had the same problem -- I was creating a base class for all non-root nodes and was looking for a succinct name. Here's what I came up with (and I realize none of these is perfect):

• NonRootNode -- this is a bit clumsy, but certainly descriptive
• ChildNode -- short, but potentially misleading
• ParentedNode -- I like this one
• NestedNode -- might work depending on the context

In the middle they're called branches. On the very ends, they're leaves.

        R
       / \
      B   L
     / \
    L   B
       /
      L

R is root, B are branches L are leaves