probing pin; probe

any circuit in which energy or matter moves in a cycle, such as an electrical circuit

to use / to employ / to make use of, to apply / to spend

look for

(archaic) spy from (a country)

fumble for, feel around for / search, investigate / enjoy the scenery

a needle used in sewing or other forms of embroidery / a phonograph needle (in record players) / a needle used in medical injections / a knitting needle / a stinger (in insects)

electron / (attributive) the quality of being electronic

question, problem on homework etc. / a question; a matter (of time etc.) / a problem (something that needs to be dealt with); a trouble / an issue; a matter

needle / pin / pointer / hand (clock) / minute hand