Today's Word of the Day means...
mineral min·er·al (mĭn'ər-əl)
A naturally occurring, homogeneous inorganic solid substance having a definite chemical composition and characteristic crystalline structure, color, and hardness.
An inorganic element, such as calcium, iron, potassium, sodium, or zinc, that is essential to the nutrition of humans, animals, and plants.
Note: Most minerals are crystals, like salt and diamonds.
Note: Rocks are aggregates of minerals.
In the diet, certain substances necessary for the maintenance of life and good health. Some are essential components of bodily substances, such as the calcium in bones and the iron in hemoglobin, whereas others help regulate the activities of metabolism. (See under “Earth Sciences.”)