the quantity of a lethal substance, as a poison or pathogen, or of ionizing radiation that will kill 50 percent of the organisms subjected to it in a specified time period. Symbol: LD50
British Dictionary definitions for median lethal dose
median lethal dose
mean lethal dose
noun
the amount of a drug or other substance that, when administered to a group of experimental animals, will kill 50 per cent of the group in a specified time
the amount of ionizing radiation that will kill 50 per cent of a population in a specified time
