Other forms: poisons
A poison is a substance that harms or kills if it gets into the body. Rat poison, a deadly poison, poison the well.
The dose is what makes it: water in quantity is a poison and a lethal chemical in traces may not be, which is the oldest principle in toxicology. Poison the well is a figure for spoiling something before anybody comes to it. The Latin behind it means a drink.
1nounpoisonA substance that harms or kills if it gets into the body.
“Keep the rat poison on a high shelf where the children can't reach it.”
poison is a substance.
Old French poison comes from Latin potio, a drink or potion, from potare, to drink.
Proto-Indo-European
*peh₃-
Latin
pōtio — drink, a draught, a poisonous draught, a potion
Old French
poison
Middle English
poysoun
English, today
poison
Built from
From Middle English poysoun, poyson, pusoun, from Old French poison, poisun, from Latin pōtio (“drink, a draught, a poisonous draught, a potion”), from pōtō (“to drink”). See also potion and potable (from the same root). Mostly displaced native Old English ātor and lybb. See more at atter.
Etymology from Wiktionary, CC BY-SA