Piracy \Pi"ra*cy\, n.; pl. Piracies. [Cf. LL. piratia, Gr. ?. See Pirate.]

1. The act or crime of a pirate.

2. (Common Law) 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.

Source: Webster's Revised Unabridged Dictionary (1913)