That may be the word definition, but malicious contact in the rule book does also account for a level of clumsiness/lack of rule understanding/poor decision making, etc.Whoa... hold on. "Malicious," by definition, requires intent. It's in the definition of the word and its root (malice).
That is a specific choice of word. It's not "hard" contact or "rough" contact. It's described as malicious contact for a reason (although, it could be the people who write the rulebooks don't understand the definition of words. It would not be the only time their poor grasp of language caused a problem).
So while the action may not be intentionally, by rule it still does fit into malicious contact. In the heat of the moment, I have seen players basically run into a player at full speed - they didn't mean to nor intend to - but they still did it and it is still malicious contact and an ejection.