Fencing with fellow before party (5)
I believe the answer is:
kendo
'fencing' is the definition.
(I've seen this before)
'fellow before party' is the wordplay.
'fellow' becomes 'ken' (I can't justify this - if you can you should give a lot more credence to this answer).
'before' means one lot of letters go next to another.
'party' becomes 'do' (do can informally mean a party).
'ken'+'do'='KENDO'
'with' is the link.
Can you help me to learn more?
(Other definitions for kendo that I've seen before include "Fighting in Japan" , "Jap. fencing with staves" , "Asian sport" , "Japanese fencing with bamboo staves" , "Japanese form of fencing" .)