1. 海盗行为；海上劫掠
Piracy is robbery at sea carried out by pirates.

2. 盗版行为；侵犯版权；非法翻印
You can refer to the illegal copying of things such as video tapes and computer programs as piracy .

1. the act of plagiarizing
taking someone's words or ideas as if they were your own

Synonym: plagiarismplagiarizationplagiarisation

2. 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

e.g. air piracy

Synonym: buccaneering