noun, masculine/pwa.zɔ̃/plural: poisons
poison is masculine in French.
poison (literal or figurative); herbicide; insecticide
“Poisson sans boisson est poison” — Fish without drink is poison (idiom)
From Old French poison f, inherited from Latin pōtiōnem f. Doublet of potion f, a borrowing. Cognate with English poison, potion.