Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.
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Question: a diode is an electronic component with two electrodes (connectors) that allows electricity to go through it in one direction and not the other direction.

Answer: diode


Question: jujutsu (柔術, jūjutsu) is an ancient japanese martial art.

Answer: jujutsu


Question: sterilisation (which some people spell sterilization) is a process that makes animals or humans that are able to bear offspring unable to do so.

Answer:
sterilisation