n. 1. A substance that causes injury, illness, or death, especially by chemical means. 2. Something destructive or fatal. 3. Chemistry A substance that inhibits another substance or a reaction: a catalyst poison. tr.v. poi·soned, poi·son·ing, poi·sons 1. To kill or harm with poison. 2. To put poison on or into: poisoning arrows; poisoned the drink. 3. b. To have a harmful influence on; corrupt: Jealousy poisoned their friendship. 4. Chemistry & Physics To inhibit (a substance or reaction). adj. Poisonous. [Middle English, from Old French, from Latin pōtiō, pōtiōn-, drink; see pō(i)- in the Appendix of Indo-European roots.] poison·er n. |
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