Joining association, pass comrade (9)
I believe the answer is:
colleague
'comrade' is the definition.
(thesaurus)
'joining association pass' is the wordplay.
'joining' says to put letters next to each other.
'association' becomes 'league' (I've seen this before).
'pass' becomes 'col' (col is a kind of pass).
'league' put after 'col' is 'COLLEAGUE'.
(Other definitions for colleague that I've seen before include "Workmate" , "Associate" , "Business co-worker" , "Person with whom one works" , "Partner" .)