B1adjective5K

Poisonous

UK /["/ˈpɔɪzənəs/"]/US /["/ˈpɔɪzənəs/"]/

Definition

causing death or illness if swallowed or taken into the body

In simple words: Something that can make you sick or kill you.

Examples

  • poisonous chemicals/fumes/plants
  • a poisonous substance
  • This gas is highly poisonous.
  • The leaves of certain trees are poisonous to cattle.
  • poisonous snakes
  • a tiny spider with a poisonous bite
  • a poisonous person
  • the poisonous atmosphere in the office

Usage notes

Use 'poisonous' to describe plants or animals that can harm people. It's appropriate in scientific contexts and everyday discussions, but be careful not to confuse it with 'venomous', which applies to animals that inject poison.

Grammar pattern

poisonous + object

Memory hint

Think of 'poison' in 'poisonous' — it's a warning sign.

Collocations

  • be
  • become
  • deadly
  • extremely
  • highly
  • to
  • be
  • become
  • deadly
  • extremely
  • highly
  • to

Synonyms

  • toxic
  • venomous

Antonyms

  • safe
  • harmless

Common mistakes

  • Confusing 'poisonous' with 'venomous'.
  • 'Poisonous' used with inanimate objects like 'poisonous gas' can be misused in some contexts.