Term: moiety
https://doi.org/10.1351/goldbook.M03968

Definition:
In physical organic chemistry moiety is generally used to signify part of a molecule, e.g. in an ester R1COOR2 the alcohol moiety is R2O. The term should not be used for a small fragment of a molecule.

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1141 (https://doi.org/10.1351/pac199466051077)

Citation: 'moiety' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03968

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