Abuse of ProcessAbuse of process is a new and relatively ill-defined doctrine, which indicates that it is a reflection of legal change in process. It has developed, and is developing, as a legal 'reason' for dealing with some underaddressed phenomenon of law. So trying to pinpoint it's essence is a bit of a mug's game, the easiest way to assess it right now is to just look for cases were judges have relied up it, and characterize those situations.
Abuse of Process Contrasted with Issue Estoppel and Res Judicata
Abuse of Process in Relation to Other Doctrine
Abuse of Process and the Rules of Civil Procedure
Abuse of Process and Criminal Procedure
Abuse of Process as a Tort