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n. Symbol H
A colorless, highly flammable element, that occurs as a diatomic molecule, H2, the lightest of all gases and the most abundant element in the universe, used in the production of synthetic ammonia and methanol, in petroleum refining, in the hydrogenation of organic materials, as a reducing atmosphere, in oxyhydrogen torches, in cryogenic research, and in rocket fuels. Atomic number 1; atomic weight 1.00794; melting point -259.1°C; boiling point -252.8°C; density at 0°C 0.08988 gram per liter; valence 1. See Periodic Table.

[French hydrogène : Greek hudro-, hydro- + French -gène, -gen.]

hy·drog′e·nous (-drōj′ə-nəs) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Chemistry) of or containing hydrogen
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(haɪˈdrɒdʒ ə nəs)

of or containing hydrogen.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The cervical, thoracic and which other vertebrae comprise the spine: Abdominal; Lumbar; Hydrogenous; Uterine?
One area it is often used is to observe the distribution of a hydrogenous material within a mineral matrix in porous media.
Its broad-based, inclusive and hydrogenous recruitments converted the state organization into a true national body being well conversant of indigenously complex social norms, taboos, trends and customs.
NMR utilizes an external magnetic field to align hydrogenous fluid component of the sample and presents number of hydrogen atoms by the amplitude of the dipole moment [31].
Transform is to transform the extracted data according to the previously designed rules and process redundant and ambiguous data so that originally hydrogenous data format can be unified.
Their molecules spread linearly in solution and have a notable tendency to aggregate by hydrogenous bonding, and consequently form colloids in solution and also tend to be adsorbed and flocculated [81].
Shields against neutrons are also usually implemented with layers of a moderating (hydrogenous) material followed by materials with a high cross-section for neutron capture.