dynamic surface tension

Synonym: dynamic interfacial tension
In certain circumstances, one may measure surface tensions that are different from the equilibrium value. Such a surface tension is called the dynamic surface (or interfacial) tension (\(\gamma ^{\text{dyn}}\) or \(\sigma ^{\mathrm{dyn}}\)). The equilibrium value is then called the static surface (or interfacial) tension (\(\gamma ^{\text{st}}\) or \(\sigma ^{\mathrm{st}}\)). The modifying signs may be omitted if there is no danger of ambiguity.
PAC, 1972, 31, 577. (Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry) on page 597 [Terms] [Paper]