Pats (4)
I believe the answer is:
taps
'pats' is the definition.
('tap' can be a synonym of 'pat')
This is all the clue.
(Other definitions for taps that I've seen before include "Strikes lightly; eavesdropping devices" , "Uses listening devices" , "Bugs; valves" , "Flow controllers" , "Knocks gently" .)