Definition: A group of chemical elements that are needed in minute quantities for the proper growth, development, and physiology of an organism. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
do not coordinate with METALS for "trace metals" nor with MINERALS for "trace minerals"; do not confuse with "tracers" used for detection or with trace amounts of substances in tissue, food, etc.
See AlsoMicronutrients