Crossword Genius

Knock Pat over (3)

Ross

I believe the answer is:

tap

'knock' is the definition.
(synonyms)

'pat over' is the wordplay.
'over' is a reversal indicator.
'pat' in reverse letter order is 'TAP'.

(Other definitions for tap that I've seen before include "Hit; bug" , "Light touch (hot or cold?)" , "indicate availability" , "Somewhere to drink beer" , "Sort of dance" .)

I've seen this clue in The Mirror.
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