Synonyms for Piracy (same or very similar meaning)
WordNet sense 1 (hijacking on the high seas or in similar contexts; taking a ship or plane away from the control of those who are legally entitled to it):
buccaneering
WordNet sense 2 (the act of plagiarizing; taking someone's words or ideas as if they were your own):
plagiarism, plagiarisation, plagiarization
From the ODE community, based on WordNet
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