LD₅₀

noun

ˌel-ˌdē-ˈfif-tē

: the amount of a toxic agent (such as a poison, virus, or radiation) that is sufficient to kill 50 percent of a population of animals usually within a certain time

Word History

Etymology

lethal dose

First Known Use

1942, in the meaning defined above

Time Traveler

The first known use of LD₅₀ was in 1942

See more words from the same year

Cite this Entry

Style

“LD50.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/LD50. Accessed 23 Mar. 2023.

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Medical Definition

LD50

noun

variants or LD₅₀

ˈel-ˈdē-ˈfif-tē

: the amount of a toxic agent (as a poison, virus, or radiation) that is sufficient to kill 50 percent of a population of animals usually within a certain time

called also median lethal dose

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