Definition of Moiety

by Anne Marie Helmenstine, Ph.D.
Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels.
Updated March 08, 2017

Definition: Moiety is a specific group of atoms within a molecule that is responsible for characteristic chemical reactions of that molecule.

Also Known As: functional group

Examples: hydroxyl moiety: -OH
aldehyde moiety: -COH