poison

v. kill or injure with toxin, give poison; have bad or damaging influence on; corrupt

n. toxin; venom

In the context of biology, poisons are substances that can cause damage, illness, or death to organisms, usually by chemical reaction or other activity on the molecular scale, when a sufficient quantity is absorbed by an organism. Paracelsus, the father of toxicology, once wrote: "Everything is poison, there is poison in everything. Only the dose makes a thing not a poison".
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Noun
1. any substance that causes injury or illness or death of a living organism
(synonym) poisonous substance
(hypernym) substance, matter
(hyponym) atropine
(derivation) envenom
2. anything that harms or destroys; "the poison of fascism"
(hypernym) destructiveness
Verb
1. spoil as if by poison; "poison someone's mind"; "poison the atmosphere in the office"
(hypernym) corrupt, pervert, subvert, demoralize, demoralise, debauch, debase, profane, vitiate, deprave, misdirect
2. kill by its poison; "This mushrooms can kill"
(hypernym) kill
(derivation) poisonous substance
3. kill with poison; "She poisoned her husband"
(hypernym) kill
(derivation) poisonous substance
4. add poison to; "Her husband poisoned her drink in order to kill her"
(synonym) envenom
(hypernym) change, alter, modify
(derivation) poisonous substance
5. administer poison to; "She poisoned her husband but he did not die"
(hypernym) drug, dose
(hyponym) intoxicate
(derivation) poisoning

n. poison, toxin, venom; bane

(v. i.)
To act as, or convey, a poison.
  

(n.)
To taint; to corrupt; to vitiate; as, vice poisons happiness; slander poisoned his mind.
  

(n.)
To put poison upon or into; to infect with poison; as, to poison an arrow; to poison food or drink.
  

(n.)
To injure or kill by poison; to administer poison to.
  

(n.)
That which taints or destroys moral purity or health; as, the poison of evil example; the poison of sin.
  

(n.)
Any agent which, when introduced into the animal organism, is capable of producing a morbid, noxious, or deadly effect upon it; as, morphine is a deadly poison; the poison of pestilential diseases.