hydrogen
/ˈhaɪdɹəd͡ʒ(ə)n/ noun
Forms hydrogens
- noun (uncountable, chemistry) The lightest chemical element (symbol H), with an atomic number of 1 and atomic weight of 1.008. “Our professor then reminded us that a hydrogen ion is merely a proton, and thus we should think about acid-base theory as we consider this problem further.”
- noun (countable) An atom of this element. “Each carbon of the ring has one hydrogen attached except for the fourth one, which is bonded to a substituent.”
- noun (uncountable) Molecular hydrogen (sense 1; symbol H₂), a colourless, odourless and flammable gas at room temperature. “A large tank of hydrogen constituted most of the bulk of that rocket.”
- noun (countable) A molecule of this molecular species.
- noun (uncountable) Synonym of protium (“the lightest and most common isotope of hydrogen (sense 1; symbol H, ¹H, or 11H), as contrasted with deuterium and tritium”). “Both hydrogen and deuterium are present in every glass of water that you drink, but the amount of deuterium is rather small.”
Synonyms
dihydrogen E949 hydrogen hydride protium element 1 hydrogen air hydrogen gas hydrogenium inflammable air waterstuff H atomic number 1
Etymology
Borrowed from French hydrogène (“hydrogen”), coined by the French chemists Louis-Bernard Guyton de Morveau (1737–1816) and Antoine Lavoisier (1743–1794) from hydro- (prefix meaning ‘water’) + -gène (suffix denoting a producer of something), from the fact that water is produced as a compound when hydrogen is oxidized.
* The prefix hydro- is borrowed from Ancient Greek ῠ̔δρο- (hŭdro-), from ῡ̆̔́δωρ (hū̆́dōr, “water”), ultimately from Proto-Indo-European *wed- (“water”).
* The suffix -gène is borrowed from Ancient Greek -γενής (-genḗs, suffix meaning ‘born in a certain condition or place’), from γένος (génos, “descendant, offspring; race; etc.”) (ultimately from Proto-Indo-European *ǵenh₁- (“to beget, produce; to give birth”)) + -ης (-ēs, suffix forming some third-declension adjectives).
By surface analysis, hydro- (prefix meaning ‘water’) + -gen (suffix denoting a producer of something).
Webster’s 1913
- noun A gaseous element, colorless, tasteless, and odorless, the lightest known substance, being fourteen and a half times lighter than air (hence its use in filling balloons), and over eleven thousand times lighter than water. It is very abundant, being an ingredient of water and of many other substances, especially those of animal or vegetable origin. It may by produced in many ways, but is chiefly obtained by the action of acids (as sulphuric) on metals, as zinc, iron, etc. It is very inflammable, and is an ingredient of coal gas and water gas. It is standard of chemical equivalents or combining
Etymology [Hydro-, 1 + -gen: cf. F. hydrogène. So called because water is generated by its combustion. See Hydra.]
Sources: Wiktionary · WordNet 3.0 · Webster’s 1913 — from the Wiktionary entry “hydrogen”, CC BY-SA 4.0. Details