- hydroelectric power.
- hydroplane.
- British.
- a bathhouse, hotel, or resort catering to people taking mineral-water health cures; spa.
- an establishment furnishing hydrotherapy.
- of, relating to, or furnishing water, water power, or hydroelectricity: funds for new hydro projects.
- a combining form meaning “water,” used in the formation of compound words: hydroplane; hydrogen.
- a combining form representing hydrogen in compound words, denoting especially a combination of hydrogen with some negative element or radical: hydrobromic.
- (esp formerly) a hotel or resort, often near a spa, offering facilities for hydropathic treatment
- short for hydroelectric
- a Canadian name for electricity when it is supplied to a residence, business, institution, etc
- (esp in Canada) a hydroelectric power company or board
- indicating or denoting water, liquid, or fluid
- indicating the presence of hydrogen in a chemical compound
- indicating a hydroid
