What is hydro prefix meaning?

The prefix hydro- means "water". It is derived from the Greek word hydōr, which means water. The use of the prefix hydro- is commonly found in scientific and technical terms related to water, such as hydrology (the study of water on Earth), hydroelectricity (electricity generated by water), and hydraulics (the study of liquids in motion). In chemistry, hydro- is used to indicate that a compound contains hydrogen, such as hydrogen chloride (HCl) and hydrocarbons (compounds made up of hydrogen and carbon atoms).