salt bridge

https://doi.org/10.1351/goldbook.09080
Means of making electrolytic connection between two half cells without introducing a significant liquid junction potential.
Note: A typical construction is a tube of an inert material (e.g. agar agar) filled with a solution containing an electrolyte with approximately equal ion mobilities of the cation and the anion (e.g., \(\ce{KNO3}\), \(\ce{KCl}\)), with the ends of the tube immersed in the electrolyte solution of the half cells.
Source:
PAC, 2020, 92, 641. (Terminology of Electrochemical Methods of Analysis (IUPAC Recommendations 2019)) on page 654 [Terms] [Paper]