Where police may have stopped car, a driver finally stepped out (5,4)
I believe the answer is:
speed trap
'where police may have stopped car' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'a driver finally stepped out' is the wordplay.
'finally' says to take the final letters.
'out' is an anagram indicator (out can mean wrong or inaccurate).
The final letter of 'driver' is 'r'.
'a'+'r'+'stepped'='arstepped'
'arstepped' is an anagram of 'SPEED TRAP'.
Can you help me to learn more?
(Other definitions for speed trap that I've seen before include "hazard for travellers in haste?" , "police operation" , "Set-up to catch fast drivers" , "Where you may see police" , "Police control" .)