Watch out! Ignoring article, Pinter play cycling without end (4,4)
I believe the answer is:
take care
'watch out' is the definition.
(thesaurus)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for take care that I've seen before include "Be cautious, mind yourself" , "Mind how you go" , "Look after yourself" , "Parting remark" , "Watch" .)