Term: substituent atom (group)
https://doi.org/10.1351/goldbook.S06076

Definition:
An atom (group) that replaces one or more hydrogen atoms attached to a parent structure or characteristic group except for hydrogen atoms attached to a chalcogen atom.

Source: Blue Book Guide, p. 13 (https://doi.org/10.1351/pac199971071327)

Citation: 'substituent atom (group)' 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.S06076

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