Joker — turn over to show face (5,2,2)
I believe the answer is:
stand up to
'face' is the definition.
(thesaurus)
'joker turn over to' is the wordplay.
'joker turn' becomes 'standup' (I can't explain this - if you can you should believe this answer much more).
'over' means one lot of letters go next to another (in a down clue, some letters go over others).
'standup'+'to'='STAND UP TO'
'show' acts as a link.
Can you help me to learn more?
(Other definitions for stand up to that I've seen before include "Resist person courageously - get off your knees" , "Brave" , "Resist (someone)" .)