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Synonyms

piracy

American  
[pahy-ruh-see] / ˈpaɪ rə si /

noun

plural

piracies
  1. practice of a pirate; robbery or illegal violence at sea.

  2. the unauthorized reproduction or use of a copyrighted book, recording, television program, patented invention, trademarked product, etc..

    The record industry is beset with piracy.

  3. Also called stream captureGeology. diversion of the upper part of one stream by the headward growth of another.


piracy British  
/ ˈpaɪrəsɪ /

noun

  1. robbery on the seas within admiralty jurisdiction

  2. a felony, such as robbery or hijacking, committed aboard a ship or aircraft

  3. the unauthorized use or appropriation of patented or copyrighted material, ideas, etc

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • antipiracy noun

Etymology

Origin of piracy

1545–55; earlier pyracie < Medieval Latin pīrātīa < Late Greek peirāteía. See pirate, -acy

Explanation

Piracy is a what pirates do: they steal stuff. If you plagiarize by stealing someone's words or ideas that’s piracy. Argh! The original sense of piracy comes from pirates — thieves who hijack other boats, taking what they please. That should help you remember that piracy means to steal someone else's work, usually their words or ideas. A writer who doesn't cite their sources is committing piracy. Piracy is plagiarism, and it is legally and morally wrong.

Keep Reading on Vocabulary.com

Vocabulary lists containing piracy

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Since the 1800s, shipping insurers have pooled together in mutual insurance clubs that sell separate coverage for losses to ships and cargo caused by war, terrorism, and piracy.

From Barron's • Mar. 2, 2026

NATO’s European navies, after years of building warships focused on dangers including piracy, smuggling and terrorism, must once again build ones designed for sub-hunting and relearn how to use them, said retired Dutch Adm.

From The Wall Street Journal • Feb. 11, 2026

"Those who profit from piracy will be held to account."

From BBC • Feb. 3, 2026

They have also become a source of something unexpected: digital piracy.

From Slate • Feb. 3, 2026

News of this came north to Gont, but the Lords of Gont were busy with their piracy and paid small heed to the woes of other lands.

From "A Wizard of Earthsea" by Ursula K. Le Guin