Pi"ra*cy (?), n.; pl. Piracies (#). [Cf. LL. piratia, Gr. . See Pirate.]
1.
The act or crime of a pirate.
2. CommonLaw
Robbery on the high seas; the taking of property from others on the open sea by open violence; without lawful authority, and with intent to steal; -- a crime answering to robbery on land.
<-- air piracy -- to commandeer or hijack an airplane -->
⇒ By statute law several other offenses committed on the seas (as trading with known pirates, or engaging in the slave trade) have been made piracy.
3.
"Sometimes used, in a quasi-figurative sense, of violation of copyright; but for this,
infringement is the correct and preferable term."
Abbott.
© Webster 1913.