1. The act, or the result of the act, of making something less completely saturated; more specifically, the percentage of total binding sites remaining unfilled; when hemoglobin is 70% saturated with oxygen and nothing else, its desaturation is 30%.
2. The process or reaction of removal of two hydrogen atoms from a molecule, resulting in the formation of a double bond.
The information shown above for desaturation is provided by Stedman's.
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