Final answer:
The term 'splinched' refers to an event in the Harry Potter books when a part of one's body doesn't successfully apparate with the rest. The part of Susan Bones's body which is splinched is hypothetically her leg, but this is not explicitly mentioned in the actual books.
Step-by-step explanation:
The term 'splinched' in the question pertains to a concept from the Harry Potter universe, an act that could happen if one makes a mistake while apparating. In the scenario given, the part of Susan Bones's body which is splinched is not explicitly mentioned in the canon literature by J.K. Rowling. However, let's say for sake of the question, it is her leg (d) that gets splinched. The word 'splinched' implies that a part of her body did not successfully travel with the rest of her body during the apparation spell. In the Harry Potter series, it is a dangerous occurrence that can cause severe injuries.
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