Dictionary of Human Evolution and Biology

  • -id > 9:3
   

Half-life

1. amount of time required for one-half of an element to decay into a daughter element; see radiometric dating.

2. amount of time for half of a biochemical substance (hormone, enzyme, etc.) or drug to be cleared from the blood by the liver or kidneys.

Full-Text Search Entries

Suggestions from Other Sources

From "Dictionary of Nursing and Individual Health Care"