Definition

Noun 1. A toxic climbing vine: "poison mercury" refers to a specific, irritating plant native to eastern and central North America. It is characterized by leaves grouped in threes, small greenish flowers, and white berries. Contact with this plant, especially its oil, causes a severe skin rash.

Usage Notes

• "Poison mercury" is the common name for a single, specific plant species (, also widely known as poison ivy). It is treated as a singular, uncountable noun when referring to the plant in general.
• It is primarily used in botanical, outdoor, or medical contexts to identify and warn about this hazardous plant.

Examples

• Identifying the plant:
  • Be careful hiking; there's poison mercury all along this trail.
  • The forest guide pointed out the poison mercury with its distinctive white berries.
• Warning about effects:
  • Brushing against poison mercury can cause an itchy, blistering rash.
  • The oil from poison mercury is highly irritating to the skin.

Advanced Usage

• The term is used descriptively in environmental and safety instructions.
  • The park service posted signs to help visitors recognize and avoid poison mercury.

Variants and Related Words

• Poison ivy (n): The much more common name for the same plant (). "Poison mercury" is a less frequently used synonym.
• Toxicodendron radicans (n): The scientific, botanical name for the plant.
• Urushiol (n): The name of the irritating oil produced by poison mercury/poison ivy that causes the allergic reaction.

Synonyms

• Poison ivy: The standard common name for the same plant.
• Markweed: A regional/common name for the same plant.

Related Phrases/Idioms

• "Leaves of three, let it be": A common warning rhyme and idiom used to help identify poison mercury/poison ivy, which always has leaves grouped in sets of three.
  • Remember the saying, "leaves of three, let it be," to avoid poison mercury.

Noun

1. climbing plant common in eastern and central United States with ternate leaves and greenish flowers followed by white berries; yields an irritating oil that causes a rash on contact