Hang on (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
wait
'hang on' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for wait that I've seen before include "Cool one's heels" , "Remain in expectation" , "Serve at table" , "Hang about" , "Serve on tables" .)