SOS! (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
help
'sos' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for help that I've seen before include "record by the Beatles" , "Contribute to the success of" , "one by the Beatles" , "Be of service" , "Serve" .)