Look up isotonic in Wiktionary, the free dictionary.
The term isotonic may refer to:
- Isotonic (exercise physiology), a type of muscle contraction
- Isotonic regression, a type of numerical analysis
- Isotonic, one of three types of tonicity that characterize a solution's concentration; see Tonicity#Isotonicity
- A sports drink that contains similar concentrations of salt and sugar to the human body