biologic half-life

biologic half-life,

the time required for the body to eliminate half of an administered dose of any substance by regular physiologic processes. The biologic half-life is approximately the same for stable and radioactive isotopes of a specific element. Also called metabolic half-life. See also effective half-life, half-life.

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half-life,

n the time in which a radioactive substance will lose half of its activity through disintegration.

half-life, biologic,

n the time in which a living tissue, organ, or individual eliminates, through biologic processes, half of a given amount of a substance that has been introduced into it.

half-life, effective,

n the half-life of a radioactive isotope in a biologic organism, resulting from the combination of radioactive decay and biologic elimination.

half-life, physical,

n the average time required for the decay of half the atoms in a given amount of a radioactive substance.