Ion-selective electrode cell in which the ion-selective electrode and reference electrode are combined in a single sensor assembly, thereby avoiding the need for a separate external reference electrode.
Source:
PAC, 2020, 92, 641. 'Terminology of Electrochemical Methods of Analysis (IUPAC Recommendations 2019)' on page 661 (https://doi.org/10.1515/pac-2018-0109)