- communication between blood vessels by means of collateral channels, especially when usual routes are obstructed.
- connection between parts of any branching system, as veinlets in a leaf or branches of a stream.
- a joining of or opening between two organs or spaces that normally are not connected.
- a natural connection between two tubular structures, such as blood vessels
- the surgical union of two hollow organs or parts that are normally separate
- the separation and rejoining in a reticulate pattern of the veins of a leaf or of branches
