From Longman Dictionary of Contemporary Englishpoison pillˌpoison ˈpill noun [countable] technical informal something in a company’s financial or legal structure that is intended to make it difficult for another company to take control of it
Examples from the Corpus
poison pill• Mackenzie put a poison pill into place, which gave the company 60 days to find another suitor.• On Wednesday, they threatened to withdraw support for a minimum wage boost if the so-called poison pill amendment passed.• And a firm's environmental history has emerged as another potential poison pill no-one wants to swallow.From Longman Business Dictionarypoison pillˌpoison ˈpill noun [countable] journalismFINANCE something in a company’s financial or legal structure that is meant to make it difficult for another company to buy it in a TAKEOVERThe company’s poison pill anti-takeover measure prevents a group from purchasing more than 10% of its stock. → see also shark repellent 