Source : Free On-Line Dictionary of Computing

strongly connected component
     
        (SCC) A subset, S, of the nodes of a {directed graph} such
        that any node in S is reachable from any other node in S and S
        is not a subset of any larger such set.  SCCs are {equivalence
        class}es under the {transitive closure} of the "directly
        connected to" {relation}.
     
        (1995-02-06)