: a substance that can cause people or animals to die or to become very sick if it gets into their bodies especially by being swallowed
: something (such as an idea, emotion, or situation) that is very harmful or unpleasant
: to cause (a person or animal) to die or to become very sick with poison
: to put a harmful or deadly substance in or on (something)
: to change (something) in a very harmful or unpleasant way
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