poison pill

American  

[poi-zuhn pil] / ˈpɔɪ zən ˌpɪl /

noun

1. Also called suicide pill.  a pellet or capsule of a quick-acting poison, as cyanide, for a spy to ingest when faced with capture or torture.

2. Financial Slang. any of various business devices created to prevent a company from being taken over by another, as issuing a new class of stock or stock warrants that would become costly to the buyer in the event of a takeover.

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poison pill British  

noun

1. finance a tactic used by a company fearing an unwelcome takeover bid, in which the value of the company is automatically reduced, as by the sale of an issue of shares having an option unfavourable to the bidders, if the bid is successful

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Etymology

Origin of poison pill

First recorded in 1945–50

Example Sentences

Beretta, which already owns about 9.95% of Sturm Ruger’s RGR 5.61%increase; green up pointing triangle outstanding common stock, asked the board to exempt the transaction from Ruger’s shareholder-rights plan, or poison pill, adopted last fall.

From The Wall Street Journal • Mar. 25, 2026

But scientists may have just discovered the poison pill needed to drive off these unwelcome dinner guests — a gluten-free option found in ancient Egyptian texts.

From Salon • May 7, 2024

The poison pill was extended on May 16 for another year.

From Reuters • Jun. 14, 2023

“They said it could be a poison pill put in the data and we really shouldn’t release the China stuff,” he said.

From Washington Post • Apr. 20, 2023

Mark this: Nature, and Nature alone, effects cures, and it's in very, very few instances that a poison pill can be used to advantage.

From Think A Book for To-day by Hunter, Col. Wm. C.