1. Of, pertaining to, affected with, or caused by a toxin or poison.
2. Acting as or having the effect of a poison; poisonous.
3. Pertaining to or noting debt that will probably not be repaid.
4. Pertaining to or noting a financial instrument or other asset that has no value or an unknown value because there is no market for it.noun
5. A toxic chemical or other substance.
EX. Wait, wait, wait. Every Pokémon can learn Toxic? I mean... that's good for the metagame, but seriously what in-game reason would this be a thing...? I suppose it is learned through a TM, so maybe it's man made but Gym Leader Koga said it was ancient. Weird.
SOURCE: RARE CANDY TREATMENT