Crossword Genius

Quick to knock with identification (5)

Ross

I believe the answer is:

rapid

'quick' is the definition.
(synonyms)

'knock with identification' is the wordplay.
'knock' becomes 'rap' (synonyms).
'with' is a charade indicator (letters next to each other).
'identification' becomes 'ID' (abbreviation).
'rap'+'id'='RAPID'

'to' is the link.

(Other definitions for rapid that I've seen before include "Fast, quick" , "Precipitate" , "Happening at great speed" , "Quickly accomplished" , "Fleet, swift" .)

I've seen this clue in The Mirror.
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