Freebase(0.00 / 0 votes)Rate this definition: Hydroelectricity. Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water.
Definition: Hormones. Hormones. Hormones are chemical substances that act like messenger molecules in the body. After being made in one part of the body, they travel to other parts of the body where they help control how cells and organs do their work. For example, insulin is a hormone that's made by the beta cells in the pancreas.
Hormones are chemical messengers that are secreted directly into the blood, which carries them to organs and tissues of the body to exert their functions. There are many types of hormones that act on different aspects of bodily functions and processes.