Quick reversing trams (5)

I believe the answer is:

smart

'quick' is the definition.
(I've seen this before)

'reversing trams' is the wordplay.
'reversing' says the letters should be written backwards.
'trams' written backwards gives 'SMART'.

(Other definitions for smart that I've seen before include "Spruce; sting" , "Bright; sting" , "Alick" , "Clever; sting" , "Chic - hurt" .)

I've seen this clue in the Evening Standard.

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