hydrogen -
a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
chemical element,
element the most favorable environment for a plant or animal; "water is the element of fishes"
gas the state of matter distinguished from the solid and liquid states by: relatively low density and viscosity; relatively great expansion and contraction with changes in pressure and temperature; the ability to diffuse readily; and the spontaneous tendency to become distributed uniformly throughout any container
h2o,
water a liquid necessary for the life of most animals and plants; "he asked for a drink of water"
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of 1.00794 u, hydrogen is the lightest and most abundant chemical element, constituting roughly 75 % of the Universe's elemental mass.
OmegaWiki Dictionary
Ω
hydrogen A flammable colourless gas that is the lightest and most abundant element in the universe. It occurs mainly in water and in most organic compounds and is used in the production of ammonia and other chemicals, in the hydrogenation of fats and oils, and in welding.
