Definitions

1. noun

a substance that is harmful or toxic to humans or animals if ingested, inhaled, or otherwise absorbed.

“The doctor warned the child not to eat the berries, which were poisonous.”

2. verb

to make (something) poisonous or to cause (someone) to become ill or to die by giving them a poisonous substance.

“The murderer poisoned the victim with a deadly dose of cyanide.”

3. adjective

having or causing the quality of being poisonous.

“The snake’s venom was highly poisonous and caused severe pain.”