What does hydrolysis mean?
Hydrolysis is a chemical process in which a substance is broken down by reaction with water. The water molecule participates in the reaction, often causing a chemical bond to be cleaved and producing smaller compounds. The term is especially important in chemistry and biochemistry: acid hydrolysis and base hydrolysis are recognized laboratory reactions, while biological hydrolysis is involved in digesting proteins, fats, and carbohydrates. In biological systems, enzymes usually control and speed up the process. Although hydrolysis can sometimes be described loosely as decomposition or splitting, the precise meaning depends on water acting as a reactant rather than merely being the medium in which a reaction occurs. The word is useful in scientific and health-related contexts because it identifies a specific mechanism by which complex molecules are converted into simpler, more usable forms.
nounThe chemical decomposition of a substance by reaction with water. In biological and biochemical contexts, the term describes the breaking down of molecules through the addition of water.
- The chemical decomposition of a substance through reaction with water, especially the cleavage of a chemical bond by water.
- In biology and biochemistry, the breakdown of a molecule involving the addition of water, as in the digestion of proteins or carbohydrates.
"Hydrolysis of proteins during digestion produces smaller peptides and amino acids."
"Salt undergoes hydrolysis when dissolved in water, producing a slightly alkaline solution."
"Enzymes accelerate the hydrolysis of carbohydrates into simpler sugars during digestion."
The word is normally used in the singular or as an uncountable process. The plural is uncommon but is used for separate hydrolysis reactions or instances.
"The researchers compared the hydrolyses of several different ester compounds."
Hydrolysis is the hidden chemical process that helps turn food, proteins, and many other complex substances into forms the body can use.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does hydrolysis come from?
The word comes from Greek hydro-, meaning “water,” and lysis, meaning “a loosening” or “breaking up.” It was coined in the 19th century as a scientific term for decomposition caused by water. Its components are reflected in related scientific words such as hydrogen, hydroxide, and lysosome, and the related process electrolysis follows the same Greek root but uses electricity rather than water to bring about decomposition.
Related word forms
How hydrolysis is actually used
This is primarily a technical term in chemistry, biochemistry, pharmacology, and related fields. In general writing, it is usually used for a chemical or biochemical process involving water.
Easily confused with hydrolysis
Hydrogenolysis breaks a chemical bond using hydrogen, whereas hydrolysis breaks a bond by reaction with water.
Dehydration removes water from a substance, while hydrolysis uses water to break a substance down.