Definition

1. Noun:
   • The amount of a substance that causes death: A "lethal dose" is the specific quantity of a drug, poison, or other chemical agent that is sufficient to kill an organism, typically a human or animal.

Usage

• The term is most commonly used in scientific, medical, and toxicological contexts to quantify toxicity.
• It is often abbreviated as LD, most frequently seen as LD50 (Lethal Dose, 50%), which refers to the dose required to kill half the members of a tested population.

Examples

• Noun:
  • The researchers calculated the lethal dose of the new compound for laboratory mice.
  • Ingesting a lethal dose of that medication can cause rapid organ failure.
  • The LD50 value is a standard measure of a substance's acute toxicity.

Advanced Usage

• "Median lethal dose (LD50)": This is the statistically derived dose at which 50% of the test population is expected to die. It is a crucial metric in toxicology.
  • The pesticide's median lethal dose (LD50) was established through rigorous testing.

Variants and Related Words

• Lethality (n): The capacity to cause death; the quality of being lethal.
  • The lethality of the venom varies by species.
• Sublethal dose (n): A dose that causes harmful effects but is not sufficient to cause death.
  • Exposure to a sublethal dose may still result in long-term health complications.

Synonyms

• Fatal dose: A dose that results in death.
• Toxic dose: A dose that causes poisoning or harmful effects (this can be broader than strictly lethal).

Related Phrases

• Lethal injection (n): A method of execution or euthanasia involving the administration of a lethal dose of drugs.
  • Lethal injection is a controversial form of capital punishment.
• Minimum lethal dose (MLD or LDmin) (n): The smallest dose that has been reported to cause death.
  • Determining the minimum lethal dose is challenging due to individual variations.

Noun

1. the size dose that will cause death