hydrogen: [18] Greek húdōr ‘water’ (a distant relative of English water) has been a prolific source of English vocabulary. Amongst its contributions are hydrangea [18] (literally ‘water-vessel’, so named from the cuplike shape of its seedpods), hydrant [19], hydrate [18], hydraulic [17] (literally ‘of a water-pipe’), hydrofoil [20], and hydroponics [20] (literally ‘water-culture’). Hydrogen itself means literally ‘generating water’, and was coined in French as hydrogène in the late 1780s for hydrogen’s property of forming water when oxidized. It is first recorded in English in 1791. => water
