It can measure current between some terminals (5)
I believe the answer is:
meter
'it can measure current' is the definition.
The definition suggests a singular noun which matches the answer.
'between some terminals' is the wordplay.
'between' indicates a hidden word.
'METER' is hidden in the letters of 'some terminals'.
Can you help me to learn more?
(Other definitions for meter that I've seen before include "Device for recording, say, usage (5)" , "Measuring device, say for electricity usage" , "Measuring device as for electricity consumption" , "Gauge" , "Measuring device as for electricity usage (5)" .)