What does hydrogen mean?

Definitions for hydrogen
ˈhaɪ drə dʒənhy·dro·gen

This dictionary definitions page includes all the possible meanings, example usage and translations of the word hydrogen.

Princeton's WordNet

  1. hydrogen, H, atomic number 1noun

    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


  1. hydrogennoun

    The lightest chemical element (symbol H) with an atomic number of 1 and atomic weight of 1.00794.

  2. hydrogennoun

    Molecular hydrogen (H), a colourless, odourless and flammable gas at room temperature.

  3. hydrogennoun

    An atom of the element.

  4. hydrogennoun

    A sample of the element.

  5. Etymology: From hydrogène, coined by Louis-Bernard Guyton de Morveau, from ὕδωρ + γεννάω.


  1. Hydrogen

    Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula H2. It is colorless, odorless, tasteless, non-toxic, and highly combustible. Hydrogen is the most abundant chemical substance in the universe, constituting roughly 75% of all normal matter. Stars such as the Sun are mainly composed of hydrogen in the plasma state. Most of the hydrogen on Earth exists in molecular forms such as water and organic compounds. For the most common isotope of hydrogen (symbol 1H) each atom has one proton, one electron, and no neutrons. In the early universe, the formation of protons, the nuclei of hydrogen, occurred during the first second after the Big Bang. The emergence of neutral hydrogen atoms throughout the universe occurred about 370,000 years later during the recombination epoch, when the plasma had cooled enough for electrons to remain bound to protons.Hydrogen is nonmetallic (except it becomes metallic at extremely high pressures) and readily forms a single covalent bond with most nonmetallic elements, forming compounds such as water and nearly all organic compounds. Hydrogen plays a particularly important role in acid–base reactions because these reactions usually involve the exchange of protons between soluble molecules. In ionic compounds, hydrogen can take the form of a negative charge (i.e., anion) where it is known as a hydride, or as a positively charged (i.e., cation) species denoted by the symbol H+. The H+ cation is simply a proton (symbol p) but its behavior in aqueous solutions and in ionic compounds involves screening of its electric charge by nearby polar molecules or anions. Because hydrogen is the only neutral atom for which the Schrödinger equation can be solved analytically, the study of its energetics and chemical bonding has played a key role in the development of quantum mechanics. Hydrogen gas was first artificially produced in the early 16th century by the reaction of acids on metals. In 1766–1781, Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance, and that it produces water when burned, the property for which it was later named: in Greek, hydrogen means "water-former". Industrial production is mainly from steam reforming of natural gas, oil reforming, or coal gasification. A small percentage is also produced using more energy-intensive methods such as the electrolysis of water. Most hydrogen is used near the site of its production, the two largest uses being fossil fuel processing (e.g., hydrocracking) and ammonia production, mostly for the fertilizer market. It can be burned to produce heat or combined with oxygen in fuel cells to generate electricity directly, with water being the only emissions at the point of usage. Hydrogen atoms (but not gaseous molecules) are problematic in metallurgy because they can embrittle many metals.


  1. hydrogen

    Hydrogen is a chemical element with the symbol H, and it is the lightest and most abundant element in the universe. It is colorless, odorless, nonmetallic, tasteless, and highly flammable in its gaseous state. Hydrogen can be found in great abundance in water, organic compounds, and in many minerals. Despite its wide occurrence, it does not occur naturally as a gas on Earth — it is always combined with other elements. Hydrogen is important in various fields, including the petroleum, chemical, and food industries. It is also a vital component in the operation of fuel cells and other forms of clean, renewable energy.

Webster Dictionary

  1. Hydrogennoun

    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 weights, and also of valence, being the typical monad. Symbol H. Atomic weight 1

  2. Etymology: [Hydro-, 1 + -gen: cf. F. hydrogne. So called because water is generated by its combustion. See Hydra.]


  1. Hydrogen

    Hydrogen is a chemical element with chemical symbol H and atomic number 1. With an atomic weight of 1.00794 u, hydrogen is the lightest element and its monatomic form is the most abundant chemical substance, constituting roughly 75% of the Universe's baryonic mass. Non-remnant stars are mainly composed of hydrogen in its plasma state. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Most of the hydrogen on Earth is in molecules such as water and organic compounds because hydrogen readily forms covalent compounds with most non-metallic elements. Hydrogen plays a particularly important role in acid–base chemistry with many reactions exchanging protons between soluble molecules. In ionic compounds, it can take a negative charge, or as a positively charged species H+. The latter cation is written as though composed of a bare proton, but in reality, hydrogen cations in ionic compounds always occur as more complex species. The most common isotope of hydrogen is protium with a single proton and no neutrons. As the simplest atom known, the hydrogen atom has been of theoretical use. For example, as the only neutral atom with an analytic solution to the Schrödinger equation, the study of the energetics and bonding of the hydrogen atom played a key role in the development of quantum mechanics.

Chambers 20th Century Dictionary

  1. Hydrogen

    hī′dro-jen, n. a gas which in combination with oxygen produces water, an elementary gaseous substance, the lightest of all known substances, and very inflammable.—adjs. Hy′dric, containing hydrogen; Hydrog′enous, containing hydrogen: produced by the action of water, as applied to rocks in opposition to those that are pyrogenous, formed by the action of fire. [A word coined by Cavendish (1766) from Gr. hydōr, water, and genēs, producing.]

U.S. National Library of Medicine

  1. Hydrogen

    Hydrogen. The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight 1. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.

The Standard Electrical Dictionary

  1. Hydrogen

    An element existing under all except the most extreme artificial conditions of pressure and cold as a gas. It is the lightest of known substances. Atomic weight, 1; molecular weight, 2; equivalent, 1; valency, 1; specific gravity, .0691-.0695. (Dumas & Boussingault.) It is a dielectric of about the same resistance as air. Its specific inductive capacity at atmospheric pressure is:     .9997 (Baltzman)   .9998 (Ayrton) Electro-chemical equivalent, .0105 milligram. The above is usually taken as correct. Other values are as follows: .010521 (Kohllrausch)   .010415 (Mascart) The electro-chemical equivalent of any element is obtained by multiplying its equivalent by the electro-chemical equivalent of hydrogen. The value .0105 has been used throughout this book.

British National Corpus

  1. Written Corpus Frequency

    Rank popularity for the word 'hydrogen' in Written Corpus Frequency: #3805

  2. Nouns Frequency

    Rank popularity for the word 'hydrogen' in Nouns Frequency: #2682

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  1. Chaldean Numerology

    The numerical value of hydrogen in Chaldean Numerology is: 5

  2. Pythagorean Numerology

    The numerical value of hydrogen in Pythagorean Numerology is: 6

Examples of hydrogen in a Sentence

  1. Frank Zappa:

    There is more stupidity then hydrogen in the universe and it has a longer shelf life.

  2. Bill Hare:

    Gas is a fossil fuel, and any investment into gas today risks becoming a stranded asset. And while interest in green hydrogen has grown exponentially, there is still a large number of hydrogen projects in the pipeline where it's produced from gas, hydrogen produced from gas still produces carbon, and is inconsistent with reaching net zero.

  3. Idi Amin:

    I propose getting rid of conventional armaments and replacing them with reasonably priced hydrogen bombs that would be distributed equally throughout the world.

  4. Harlan Ellison:

    The two most common elements in the universe are Hydrogen and stupidity.

  5. Cynthia Selin:

    Continued investment and favorable policy conditions … mean that clean hydrogen( including hydrogen made using renewable energy) could see sustained growth, the development of necessary infrastructure, and better cost competitiveness, in terms of consumer-facing developments in relation to hydrogen, in ’23 the most likely area of attention will be in long-haul trucking.

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Translations for hydrogen

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"hydrogen." Definitions.net. STANDS4 LLC, 2023. Web. 10 Dec. 2023. <https://www.definitions.net/definition/hydrogen>.

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    greatly exceeding bounds of reason or moderation
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