hydrantPronunciation: /ˈhʌɪdr(ə)nt/Translate hydrant | into French | into German | into Italian | into Spanish Definition of hydrant noun a water pipe, especially one in a street, with a nozzle to which a fire hose can be attached. Origin: early 19th century (originally US): formed irregularly from hydro- 'relating to water' + -anthydrant in other Oxford dictionaries Definition of hydrant in the US English dictionary