poison pill

noun
  1. a pellet of a quick-acting poison, as cyanide, for a spy to carry in order to commit suicide 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.

Origin of poison pill

First recorded in 1945–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for poison pill

poison pill

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
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