See you run twice (3-3)
I believe the answer is:
bye-bye
'see you' is the definition.
(I've seen this before)
'run twice' is the wordplay.
'run' becomes 'bye' (type of cricket run).
'twice' says to double the letters.
'bye' doubled is 'BYE-BYE'.
(Other definitions for bye-bye that I've seen before include "So long" , "See you" , "Au revoir for juniors?" , "Ta-ta" , "Cheerio" .)