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Synonyms

insider trading

American  

noun

  1. the illegal buying and selling of securities by persons acting on privileged information.

insider trading Cultural  

  1. The unlawful practice of using information that comes from a source “inside” the business but is not available to the general public to trade on the stock market. This activity is prohibited by law and is policed by the Securities and Exchange Commission.

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In the mid-1980s, several revelations of insider trading rocked Wall Street.

Other Word Forms

  • insider trader noun

Etymology

Origin of insider trading

First recorded in 1965–70

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.

In traditional financial markets, insider trading is widely agreed to be bad and understood to be illegal.

From Slate • Apr. 24, 2026

Concerns have risen about the potential ease of insider trading on the betting platforms as increasing numbers of people have taken their chances at predicting future results.

From MarketWatch • Apr. 23, 2026

Soon after the incident, Polymarket explicitly prohibited insider trading and market manipulation on its international platform for the first time.

From The Wall Street Journal • Apr. 23, 2026

None of the US financial authorities contacted by the BBC acknowledged any of the allegations of insider trading.

From BBC • Apr. 19, 2026

Paolo’s father was a real estate mogul who had been indicted for insider trading some months ago.

From "Genuine Fraud" by E. Lockhart

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.