pH glass electrode

https://doi.org/10.1351/goldbook.P04545
A hydrogen-ion responsive electrode usually consisting of a bulb, or other suitable form, of special glass attached to a stem of high
resistance
glass complete with
internal reference electrode
and
internal filling solution
system. Other geometrical forms may be appropriate for special applications, e.g. capillary electrode for measurement of blood
pH
.
Source:
PAC, 1985, 57, 531. (Definition of pH scales, standard reference values, measurement of pH and related terminology (Recommendations 1984)) on page 540 [Terms] [Paper]