Answer:
accidental
Explanation:
Deaths which are caused due to accidents are called accidental deaths. Accidental deaths are unintentional and unavoidable. In the United States alone, accidental deaths caused nearly 40 percent of deaths.
In the context, John had an argument with Janet and he hits Janet's head with the bar stool. John did not do it intentionally with the thought of killing Janet but it was an action caused in the argument. Janet was fine until two months later he died due to internal bleeding from the skull.
Thus this was an accidental death in which Janet died due to internal bleeding in the skull which was caused by the unintentional action of John two months ago.