Detector of speeding Lada cutting off learner in posh car (5)
I believe the answer is:
radar
'detector' is the definition.
(I've seen this before)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for radar that I've seen before include "Electronic detection system" , "Kind of gun" , "Range-finding and detection system" , "Remote detection device" , "Pulse detection system" .)