n. the chemical reaction of hydrogen with another substance, especially with an unsaturated organic compound, and usually under the influence of temperature, pressure and catalysts.
the GNU version of the Collaborative International Dictionary of English
n. The act of combining with hydrogen, or the state of being so combined.
The Century Dictionary and Cyclopedia
n. The act of hydrogenating, or the state of being hydrogenated.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a chemical process that adds hydrogen atoms to an unsaturated oil
Word Usage
"This process is called hydrogenation, because it adds hydrogen atoms to the unsaturated chains."