Turn over bar for party (5)
I believe the answer is:
revel
'party' is the definition.
(thesaurus)
'turn over bar' is the wordplay.
'turn' becomes 'rev' (I've seen this before).
'over bar' becomes 'el' (I can't justify this - if you can you should give a lot more credence to this answer).
'rev'+'el'='REVEL'
'for' is the link.
Can you help me to learn more?
(Other definitions for revel that I've seen before include "Celebrate with a lever, strangely" , "Lever (anag.)" , "Take great delight (in)" , "Be festive, enjoy" , "Have noisy fun" .)