poison sumac

1 8.4

A North American shrub or small tree with white berries and an oil that causes a skin rash

noun
/ˈpɔɪzən ˈsuːmæk/

: sumaque venenoso

Examples

I'll bet a lot of these men never even heard of poison sumac.

Fiction book (1991)
Do you know that the oil, the reason that Poison Ivy, poison oak and poison sumac all give you this rash is because they all have an oil called urishiol.
She looked for the shiny leaves that meant poison ivy, poison oak, or poison sumac, and didn't see any... thank God for small favors.

Fiction book (2000)
Poison sumac has poison sumac leaves that can cause a painful skin rash if touched.
The garden was filled with poison sumac, making it unsafe for anyone to explore.
You should avoid poison sumac because its oil can irritate your skin.

Synonyms

Toxicodendron vernix

vspoison sumac

Specialized

9.9

A swamp bush with smooth branches and pale berries whose oil causes a skin rash

is the common name form used instead of the scientific term

Rhus vernix

vspoison sumac

Specialized

9.9

A shrub also called poison sumac that grows in swamps and makes an oil causing itchy skin rashes

is the common name form used instead of the scientific label

How Irritating

poison sumac

1 8.4

irritant

15 6.0

Surface Forms

poison sumac singular

poison sumacs plural

Morphology

poison + sumac

The noun phrase is directly compositional: 'poison' (harmful or causing injury) modifies 'sumac' (a type of plant), so a learner who knows both words can infer it is a sumac plant that is poisonous or causes skin irritation. This follows the common English pattern seen in compounds like 'poison ivy' or 'poison oak', making the meaning predictable for B1 learners.

Etymology

The name poison sumac puts poison before sumac as a clear warning: when people touch this plant it releases an oily sap that makes the skin very red and itchy. So, the name now means a 'harmful to touch' plant that causes a bad skin rash.